Solution : https://service.sap.com/sap/support/notes/372419 (SAP Service marketplace login required)
Key words :
additional key words screen layout, field selection group pt9f, field selection group 'quantity, field selection pt9f, external services functionality, produce undesired effects, external service items, purchase order increases, po item overview, field 'quantity'
Related Notes :
| 634395 | FAQ: Purchase orders in the service |