Oracle Message PGA-20924 - unable to enter send state for deallocate, state = number (string)

ERRORunable to enter send state for deallocate, state = number (string)
CAUSEThe gateway was unable to enter send state to perform a normal deallocation. The conversation state is , and its descriptive name is . The conversation states are documented in the /usr/include/cmc.h header file.
ACTIONThis is usually a problem with the remote transaction program or a problem with the network. Check the remote system for diagnostic information. The gateway will perform an abnormal deallocation after this error has been encountered.