Solution : https://service.sap.com/sap/support/notes/103714 (SAP Service marketplace login required)
Key words :
additional key words atp, change type group 'level', type group, exit transactions, availability check, quantity locks, table atpenq, lock server, incorrect results, transaction sm12
Related Notes :
| 166261 | V_RA: Changes are not saved |
| 99999 | ATP server: Installation and sizing |