diff --git a/gradle.properties b/gradle.properties
index 2bc2ab9..007f94e 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,2 +1,2 @@
 group=org.web3j
-version=4.6.0-SNAPSHOT
+version=4.7.0-SNAPSHOT
diff --git a/src/main/java/org/web3j/quorum/UnixSocketClient.java b/src/main/java/org/web3j/quorum/UnixSocketClient.java
index c84fd5d..26a9dbf 100644
--- a/src/main/java/org/web3j/quorum/UnixSocketClient.java
+++ b/src/main/java/org/web3j/quorum/UnixSocketClient.java
@@ -40,7 +40,7 @@ public static void main(String[] args) {
                         .build();
 
         RequestBody requestBody =
-                RequestBody.create(okhttp3.MediaType.parse("application/json"), PAYLOAD);
+                RequestBody.create(PAYLOAD, okhttp3.MediaType.parse("application/json"));
 
         // use a proper host name as a DNS lookup still occurs (localhost should suffice)
         Request request =
diff --git a/src/main/java/org/web3j/quorum/tx/ClientTransactionManager.java b/src/main/java/org/web3j/quorum/tx/ClientTransactionManager.java
index c50562e..7123f1a 100644
--- a/src/main/java/org/web3j/quorum/tx/ClientTransactionManager.java
+++ b/src/main/java/org/web3j/quorum/tx/ClientTransactionManager.java
@@ -111,6 +111,19 @@ public EthSendTransaction sendTransaction(
         return sendTransaction(gasPrice, gasLimit, to, data, value);
     }
 
+    @Override
+    public EthSendTransaction sendTransactionEIP1559(
+            BigInteger gasPrice,
+            BigInteger feeCap,
+            BigInteger gasLimit,
+            String to,
+            String data,
+            BigInteger value,
+            boolean constructor)
+            throws IOException {
+        throw new UnsupportedOperationException("sendTransactionEIP1559 is not available");
+    }
+
     @Override
     public String sendCall(String to, String data, DefaultBlockParameter defaultBlockParameter)
             throws IOException {
diff --git a/src/main/kotlin/org/web3j/quorum/enclave/protocol/EnclaveService.kt b/src/main/kotlin/org/web3j/quorum/enclave/protocol/EnclaveService.kt
index 069b600..3a8571f 100644
--- a/src/main/kotlin/org/web3j/quorum/enclave/protocol/EnclaveService.kt
+++ b/src/main/kotlin/org/web3j/quorum/enclave/protocol/EnclaveService.kt
@@ -15,9 +15,9 @@ package org.web3j.quorum.enclave.protocol
 import com.fasterxml.jackson.annotation.JsonInclude
 import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
 import okhttp3.MediaType.Companion.toMediaTypeOrNull
+import okhttp3.RequestBody.Companion.toRequestBody
 import okhttp3.OkHttpClient
 import okhttp3.Request
-import okhttp3.RequestBody
 import org.web3j.quorum.enclave.EnclaveClientConnectionException
 
 /**
@@ -36,7 +36,7 @@ class EnclaveService(private val url: String, private val port: Int, private val
     fun <S, T> send(request: S, path: String, responseType: Class<T>): T {
         val payload = objectMapper.writeValueAsString(request)
         val uri = "$url:$port/$path"
-        val body = RequestBody.create(JSON_MEDIA_TYPE, payload)
+        val body = payload.toRequestBody(JSON_MEDIA_TYPE)
         val buildRequest = Request.Builder()
                 .url(uri)
                 .post(body)