Help me I am getting this error using soap UI

I built a webservice on my own :-), using WCF

I tried to access using and invoking ... I see this response...

HTTP/1.1 415 Cannot process the message because the content type 'application/soap+xml;charset=UTF-8;action="http://tempuri.org/IMyService/AddresService"' was not the expected type 'text/xml; charset=utf-8'.

How should I fix ...