SAP Message CACSSESMD014 - Incorrect call of function module &

Diagnosis
A specific commission contract is currently being processing. At thesame time, external data transfer (EDT) is attempting to access the samecontract by Direct Input.This is not permitted.

System Response
The transaction was terminated.

Procedure for System Administration
This may be the result of a lock problem (while calling function moduleENQUEUE_ECACS_CONTR).