Service Group Deployment Issue

Hi I am try to deploy service group deploy

but I am getting this error message,

can anybody give me some suggestions.

The port ‘TestServiceGroup’ could not be deployed.\nError:
c:\Users\969440100\AppData\Local\Temp\ServiceGeneration\ItestMethodServiceExecuteMethodResponse.cs(16,48) : error CS0246: The type or namespace name ‘MethodDataContract’ could not be found (are you missing a using directive or an assembly reference?)