blank qualifier not being recognised

:frowning: can someone help…blank qualifiers not being recognised on incoming files

Trd/partner : 00100306501 App. ref: INVOIC Sender ref: 457
File ref . : 000633226 File sts: Translated Errors
EDI data:
UNA:+.? ’
UNB+UNOC:3+RBEDA02::6580+5013546003650+150520:2326+457’
UNH+1+INVOIC:D:07A:UN:GAVA11’

ISC.0082.9293…no matching choice value…can you suggest how to get webmethods to recognise this…thx Jayne