Solution : https://service.sap.com/sap/support/notes/116276 (SAP Service marketplace login required)
Key words :
system generates error message gb309 'expression, system generates error message gb555, 'character string 'n1-n2, additional key words ggb0, error message gb008, conversion routine 'alpha', error message, program error, conversion routine, <table> $field
Related Notes :
| 351634 | Sub-fields or LIKE with WBS element (POSID) |
| 77268 | Conversion of sub-fields not correct |