Communicating back to WCF Service – Published Schema Req/Resp

I ran the WCF Service publishing wizard with a request/response.  For example, the method is GetData, the incoming schema is GetDataReq and the outgoing schema is GetDataResp.

I have an orchestration picking up the data.  It’s using direct binding and a filter, and that’s working.
Then the orchestration does it’s work and tries to send a message back to the same port. 

I am using correlation, but not sure I need to.

However, on the correlation, I get this error:

Description:
A response message for two-way receive port “Wcf_CustodianService_GetCustodianDocumentException” is being suspended as the messaging engine could not correlate the response to an existing request message. This usually happens when the host process has been recycled. 
 
Any ideas?
Thanks,
Neal