Operation '{0}' of contract '{1}' specifies MessageContract type '{2}' which has IsWrapped as false but has multiple request ...

Operation '{0}' of contract '{1}' specifies MessageContract type '{2}' which has IsWrapped as false but has multiple request body parameters. At most one body parameter can be serialized without wrapper elements. Either remove the extra body parameters or set the IsWrapped property on the MessageContractAttribute to true.