Solution : https://service.sap.com/sap/support/notes/193822 (SAP Service marketplace login required)
Key words : 
additional key words rhumst_hrpadnn_hrpaduzrhumst_hrpaduzabap runtime errors perform_conflict_typeprotocol_xpra_2, abap runtime errors perform_conflict_type occur, conversion report rhumst_hrpaduz, call form protocol_xpra_2, problem occurs due, text element ums, text element, termination occurs, program rhumst_hrpadnn_hrpaduz, type conflict
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