Solution : https://service.sap.com/sap/support/notes/551238 (SAP Service marketplace login required)
Key words :
find correction instructions attached, incorrect error message, business agreement class, business agreement, message r1351, message handler, termination occurs, system issues, number ranges, table crmc_buag_class
Related Notes :
| 549318 | Business agreement created w/o business agreement class |
| 513124 | Different errors with BAPIs for business agreement |