diff --git a/src/Modules/Microsoft.Azure.Functions.PowerShellWorker/Microsoft.Azure.Functions.PowerShellWorker.psm1 b/src/Modules/Microsoft.Azure.Functions.PowerShellWorker/Microsoft.Azure.Functions.PowerShellWorker.psm1
index c87f08b6..ba2a6373 100644
--- a/src/Modules/Microsoft.Azure.Functions.PowerShellWorker/Microsoft.Azure.Functions.PowerShellWorker.psm1
+++ b/src/Modules/Microsoft.Azure.Functions.PowerShellWorker/Microsoft.Azure.Functions.PowerShellWorker.psm1
@@ -160,7 +160,7 @@ function Stop-DurableOrchestration {
 
     $requestUrl = "$($DurableClient.BaseUrl)/instances/$InstanceId/terminate?reason=$([System.Web.HttpUtility]::UrlEncode($Reason))"
 
-    Invoke-RestMethod -Uri $requestUrl
+    Invoke-RestMethod -Uri $requestUrl -Method 'POST'
 }
 
 function IsValidUrl([uri]$Url) {
diff --git a/test/E2E/Azure.Functions.PowerShellWorker.E2E/Azure.Functions.PowerShellWorker.E2E/DurableEndToEndTests.cs b/test/E2E/Azure.Functions.PowerShellWorker.E2E/Azure.Functions.PowerShellWorker.E2E/DurableEndToEndTests.cs
index 6ddd58a9..19a644d1 100644
--- a/test/E2E/Azure.Functions.PowerShellWorker.E2E/Azure.Functions.PowerShellWorker.E2E/DurableEndToEndTests.cs
+++ b/test/E2E/Azure.Functions.PowerShellWorker.E2E/Azure.Functions.PowerShellWorker.E2E/DurableEndToEndTests.cs
@@ -693,7 +693,7 @@ private async Task ExternalEventClientSendsExternalEvents() {
             }
         }
 
-        [Fact(Skip = "https://github.com/Azure/azure-functions-powershell-worker/issues/640")]
+        [Fact]
         public async Task DurableClientTerminatesOrchestration()
         {
             var initialResponse = await Utilities.GetHttpTriggerResponse("DurableClientTerminating", queryString: string.Empty);