Solution : https://service.sap.com/sap/support/notes/112817 (SAP Service marketplace login required)
Key words : 
additional key words jobparallel processing, function module co_fw_affw_post occasionally, solution correct program coruafwp, function module co_fw_affw_post, error message m7021, internal table m7021_tab, post goods movements, update termination occurs, incorrect goods movements, program coruafwp
Related Notes : 
       
| 147954 | CORUAFWP: Dump or double goods movement |