Solution : https://service.sap.com/sap/support/notes/987089 (SAP Service marketplace login required)
Key words :
sales method' valid, /dbm/co_ac_repost_line_item reason, related cost repostings, dbm service orders, service order, internal orders, posting date, wrong period, terms k_23d_execute_reposting, invoice recipients
Related Notes :
| 837977 | KB61: No module for reposting |