SAP Message UMM_CUSTDATA011 - Wall '&1' or one of its subobjects is locked by &2

Diagnosis You have attempted to open wall "&V1&". This object (or one of itssubobjects) is currently being processed by user "&V2&" and is,therefore locked for other users. System Response The object remains locked exclusively for user "&V2&" until this userfinishes processing. Procedure Try to open the wall later or contact the current user "&V2&".