3635504 - An error occurs (Message No. /SCWM/WHO302) while confirming warehouse task by IDOC /SCWM/WMTOCO

User executes standard IDOC /SCWM/WMTOCO received from subsystem to confirm warehouse tasks in SAP EWM. The subsystem sends multiple single /SCWM/WMTOCO in parallel to confirm all warehouse tasks contained in the same warehouse order.
However, when received in SAP, only the first IDOC is correctly processed, confirming only one WT in the WO. Further IDOCs are in error with the following error message: Warehouse order X is already being processed by user XX (Message No. /SCWM/WHO302).
Multiple /SCWM/WMTOCO IDOCS can not be processed at the same time for the same warehouse order.

SAP Extended Warehouse Management (SCM-EWM)

/SCWM/WHO302; IDOC; /SCWM/WMTOCO; Subsystem , KBA , SCM-EWM-IF-WCU , Interface Warehouse Control Units , Problem