diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/Messaging/InvoiceRequest.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/Messaging/InvoiceRequest.cs
new file mode 100644
index 00000000..d97facc1
--- /dev/null
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/Messaging/InvoiceRequest.cs
@@ -0,0 +1,70 @@
+namespace FikaAmazonAPI.AmazonSpApiSDK.Models.Messaging
+{
+    using System;
+    using System.Linq;
+    using System.Text;
+    using Newtonsoft.Json;
+    using System.Collections.Generic;
+    using System.Runtime.Serialization;
+    using System.ComponentModel.DataAnnotations;
+
+    [DataContract]
+    public partial class InvoiceRequest : IEquatable<InvoiceRequest>, IValidatableObject
+    {
+        public InvoiceRequest(List<Attachment> attachments = default(List<Attachment>), DateTime? coverageStartDate = default(DateTime?), DateTime? coverageEndDate = default(DateTime?))
+        {
+            this.Attachments = attachments;
+        }
+
+        [DataMember(Name = "attachments", EmitDefaultValue = false)]
+        public List<Attachment> Attachments { get; set; }
+
+        public override string ToString()
+        {
+            var sb = new StringBuilder();
+            sb.Append("class InvoiceRequest {\n");
+            sb.Append("  Attachments: ").Append(Attachments).Append("\n");
+            sb.Append("}\n");
+            return sb.ToString();
+        }
+
+        public virtual string ToJson()
+        {
+            return JsonConvert.SerializeObject(this, Formatting.Indented);
+        }
+
+        public override bool Equals(object input)
+        {
+            return this.Equals(input as InvoiceRequest);
+        }
+
+        public bool Equals(InvoiceRequest input)
+        {
+            if (input == null)
+                return false;
+
+            return
+                (
+                    this.Attachments == input.Attachments ||
+                    this.Attachments != null &&
+                    this.Attachments.SequenceEqual(input.Attachments)
+                );
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked // Overflow is fine, just wrap
+            {
+                int hashCode = 41;
+                if (this.Attachments != null)
+                    hashCode = hashCode * 59 + this.Attachments.GetHashCode();
+                return hashCode;
+            }
+        }
+
+        IEnumerable<System.ComponentModel.DataAnnotations.ValidationResult> IValidatableObject.Validate(ValidationContext validationContext)
+        {
+            yield break;
+        }
+    }
+}
\ No newline at end of file
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/Messaging/InvoiceResponse.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/Messaging/InvoiceResponse.cs
new file mode 100644
index 00000000..30358cd9
--- /dev/null
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/Messaging/InvoiceResponse.cs
@@ -0,0 +1,74 @@
+namespace FikaAmazonAPI.AmazonSpApiSDK.Models.Messaging
+{
+    using System;
+    using System.Text;
+    using Newtonsoft.Json;
+    using System.Collections.Generic;
+    using System.Runtime.Serialization;
+    using System.ComponentModel.DataAnnotations;
+
+    [DataContract]
+    public partial class InvoiceResponse : IEquatable<InvoiceResponse>, IValidatableObject
+    {
+        public InvoiceResponse(ErrorList errors = default(ErrorList))
+        {
+            this.Errors = errors;
+        }
+
+        public InvoiceResponse()
+        {
+            this.Errors = default(ErrorList);
+        }
+
+        [DataMember(Name = "errors", EmitDefaultValue = false)]
+        public ErrorList Errors { get; set; }
+
+        public override string ToString()
+        {
+            var sb = new StringBuilder();
+            sb.Append("class InvoiceResponse {\n");
+            sb.Append("  Errors: ").Append(Errors).Append("\n");
+            sb.Append("}\n");
+            return sb.ToString();
+        }
+
+        public virtual string ToJson()
+        {
+            return JsonConvert.SerializeObject(this, Formatting.Indented);
+        }
+
+        public override bool Equals(object input)
+        {
+            return this.Equals(input as InvoiceResponse);
+        }
+
+        public bool Equals(InvoiceResponse input)
+        {
+            if (input == null)
+                return false;
+
+            return
+                (
+                    this.Errors == input.Errors ||
+                    (this.Errors != null &&
+                    this.Errors.Equals(input.Errors))
+                );
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked
+            {
+                int hashCode = 41;
+                if (this.Errors != null)
+                    hashCode = hashCode * 59 + this.Errors.GetHashCode();
+                return hashCode;
+            }
+        }
+
+        IEnumerable<System.ComponentModel.DataAnnotations.ValidationResult> IValidatableObject.Validate(ValidationContext validationContext)
+        {
+            yield break;
+        }
+    }
+}
\ No newline at end of file
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/AvailableValueAddedServiceGroupList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/AvailableValueAddedServiceGroupList.cs
index c43b7136..107e4e2f 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/AvailableValueAddedServiceGroupList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/AvailableValueAddedServiceGroupList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of value-added services available for a shipping service offering.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class AvailableValueAddedServiceGroupList : List<AvailableValueAddedServiceGroup> {
 
     /// <summary>
@@ -32,5 +32,5 @@ public override string ToString()  {
       return JsonConvert.SerializeObject(this, Formatting.Indented);
     }
 
-}
+  }
 }
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/ChargeList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/ChargeList.cs
index b1376342..1af784c1 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/ChargeList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/ChargeList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of charges based on the shipping service charges applied on a package.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class ChargeList : List<ChargeComponent> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/IneligibleRateList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/IneligibleRateList.cs
index 4ac44e70..0711d96a 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/IneligibleRateList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/IneligibleRateList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of ineligible shipping service offerings.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class IneligibleRateList : List<IneligibleRate> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/ItemList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/ItemList.cs
index dd87d103..112b0d9d 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/ItemList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/ItemList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of items.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class ItemList : List<Item> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageDocumentDetailList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageDocumentDetailList.cs
index a32dab7a..9993ed19 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageDocumentDetailList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageDocumentDetailList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of post-purchase details about a package that will be shipped using a shipping service.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class PackageDocumentDetailList : List<PackageDocumentDetail> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageDocumentList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageDocumentList.cs
index 1e3250c5..dd9bb50a 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageDocumentList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageDocumentList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of documents related to a package.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class PackageDocumentList : List<PackageDocument> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageList.cs
index 8d987e10..a3a1f91d 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PackageList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of packages to be shipped through a shipping service offering.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class PackageList : List<Package> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PrintOptionList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PrintOptionList.cs
index cfa12b48..fa785e91 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PrintOptionList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/PrintOptionList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of the format options for a label.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class PrintOptionList : List<PrintOption> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/RateList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/RateList.cs
index 85b3c7a2..0a1dccba 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/RateList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/RateList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of eligible shipping service offerings.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class RateList : List<Rate> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/RequestedValueAddedServiceList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/RequestedValueAddedServiceList.cs
index 5e271045..3a3eac0b 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/RequestedValueAddedServiceList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/RequestedValueAddedServiceList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// The value-added services to be added to a shipping service purchase.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class RequestedValueAddedServiceList : List<RequestedValueAddedService> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/SupportedDocumentSpecificationList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/SupportedDocumentSpecificationList.cs
index bbfde7aa..b51c39d1 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/SupportedDocumentSpecificationList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/SupportedDocumentSpecificationList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of the document specifications supported for a shipment service offering.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class SupportedDocumentSpecificationList : List<SupportedDocumentSpecification> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/TaxDetailList.cs b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/TaxDetailList.cs
index e0063c54..049d0421 100644
--- a/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/TaxDetailList.cs
+++ b/Source/FikaAmazonAPI/AmazonSpApiSDK/Models/ShippingV2/TaxDetailList.cs
@@ -10,7 +10,7 @@ namespace FikaAmazonAPI.AmazonSpApiSDK.Models.ShippingV2 {
   /// <summary>
   /// A list of tax detail information.
   /// </summary>
-  [DataContract]
+  [CollectionDataContract]
   public class TaxDetailList : List<TaxDetail> {
 
     /// <summary>
diff --git a/Source/FikaAmazonAPI/Services/ApiUrls.cs b/Source/FikaAmazonAPI/Services/ApiUrls.cs
index 3d9e43b0..c9f590c8 100644
--- a/Source/FikaAmazonAPI/Services/ApiUrls.cs
+++ b/Source/FikaAmazonAPI/Services/ApiUrls.cs
@@ -177,6 +177,7 @@ protected class MessaginApiUrls
             public static string GetAttributes(string amazonOrderId) => $"{_resourceBaseUrl}/orders/{amazonOrderId}/attributes";
             public static string CreateDigitalAccessKey(string amazonOrderId) => $"{_resourceBaseUrl}/orders/{amazonOrderId}/messages/digitalAccessKey";
             public static string CreateUnexpectedProblem(string amazonOrderId) => $"{_resourceBaseUrl}/orders/{amazonOrderId}/messages/unexpectedProblem";
+            public static string SendInvoice(string amazonOrderId) => $"{_resourceBaseUrl}/orders/{amazonOrderId}/messages/invoice";
         }
         protected class EasyShip20220323
         {
diff --git a/Source/FikaAmazonAPI/Services/MessagingService.cs b/Source/FikaAmazonAPI/Services/MessagingService.cs
index b9f00958..e3bedc41 100644
--- a/Source/FikaAmazonAPI/Services/MessagingService.cs
+++ b/Source/FikaAmazonAPI/Services/MessagingService.cs
@@ -194,7 +194,18 @@ public async Task<bool> CreateUnexpectedProblemAsync(string amazonOrderId, Creat
             return false;
         }
 
+        public bool SendInvoice(string amazonOrderId, InvoiceRequest invoiceRequest) =>
+    Task.Run(() => SendInvoiceAsync(amazonOrderId, invoiceRequest)).ConfigureAwait(false).GetAwaiter().GetResult();
+        public async Task<bool> SendInvoiceAsync(string amazonOrderId, InvoiceRequest invoiceRequest, CancellationToken cancellationToken = default)
+        {
+            List<KeyValuePair<string, string>> queryParameters = new List<KeyValuePair<string, string>>();
+            queryParameters.Add(new KeyValuePair<string, string>("marketplaceIds", AmazonCredential.MarketPlace.ID));
+            await CreateAuthorizedRequestAsync(MessaginApiUrls.SendInvoice(amazonOrderId), RestSharp.Method.Post, queryParameters, postJsonObj: invoiceRequest, cancellationToken: cancellationToken);
 
-
+            var response = await ExecuteRequestAsync<InvoiceResponse>(RateLimitType.Messaging_CreateUnexpectedProblem, cancellationToken);
+            if (response != null)
+                return true;
+            return false;
+        }
     }
-}
+}
\ No newline at end of file
diff --git a/Source/FikaAmazonAPI/Services/ShippingServiceV2.cs b/Source/FikaAmazonAPI/Services/ShippingServiceV2.cs
index 23c0727f..2a8f518b 100644
--- a/Source/FikaAmazonAPI/Services/ShippingServiceV2.cs
+++ b/Source/FikaAmazonAPI/Services/ShippingServiceV2.cs
@@ -17,7 +17,7 @@ public bool CancelShipment(string shipmentId) =>
             Task.Run(() => CancelShipmentAsync(shipmentId)).ConfigureAwait(false).GetAwaiter().GetResult();
         public async Task<bool> CancelShipmentAsync(string shipmentId, CancellationToken cancellationToken = default)
         {
-            await CreateAuthorizedRequestAsync(ShippingApiV2Urls.CancelShipment(shipmentId), RestSharp.Method.Post, cancellationToken: cancellationToken);
+            await CreateAuthorizedRequestAsync(ShippingApiV2Urls.CancelShipment(shipmentId), RestSharp.Method.Put, cancellationToken: cancellationToken);
             var response = await ExecuteRequestAsync<CancelShipmentResponse>(RateLimitType.ShippingV2_CancelShipment, cancellationToken);
             if (response != null)
                 return true;