diff --git a/APIMatic.Core/APIMatic.Core.csproj b/APIMatic.Core/APIMatic.Core.csproj
index e951f270..116b2fea 100644
--- a/APIMatic.Core/APIMatic.Core.csproj
+++ b/APIMatic.Core/APIMatic.Core.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
         <TargetFramework>netstandard2.0</TargetFramework>
@@ -37,7 +37,7 @@
             <PrivateAssets>all</PrivateAssets>
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
         </PackageReference>
-        <PackageReference Include="System.Collections.Immutable" Version="7.0.0" />
+        <PackageReference Include="System.Collections.Immutable" Version="9.0.5" />
         <PackageReference Include="Newtonsoft.Json" Version="[13.0.1,)" />
     </ItemGroup>
     <ItemGroup>