Solution : https://service.sap.com/sap/support/notes/924097 (SAP Service marketplace login required)
Key words :
expense/revenue account assignment correct' reason, error issues error message ff796, post parked documents, vendor line item, customer line item, delete item function, ff796'tax amount, attached program correctionsorenter, program error, tax amount
Related Notes :
| 962639 | Message FF 796 using FBV0 (parked document change) |
| 885799 | DYNPRO_FIELD_CONVERSION with manual tax in the vendor |