CRM 2011 RollUp 14 : Request not supported: ExecuteMultiple

I have simple method which wrap bulk entity and send to crm via

ExecuteMultipleRequest

With previous Rollup 12 it works OK, now it is broken.

Error message:

Request not supported: ExecuteMultiple

There is no error when I change send them to crm one by one so I guess it is not the data issue.

Does any encounter same issue?