Siri,
Please see the EDIModuleUserguide for documentation of convertToValues service.
The error you are getting is related to 856 parsing fail against FFSChema.
Regarding convertToValues inputs (map edidata,specify FFSchema,if possible fill the delimiters) and output map EDIValues to 846DT(use DocumentReference and locate your 856 document (856DT–this will be created using EDIFFSchema T856 (you will see the icon in the FFSChema editor to generate this document type).
If you created the EDI 856 test file,make sure the segments/fields/delimiters are appropriate to T856 Schema,then only convertToValues can parse 856 edidata successfully.
PS:If you are new to webMethods EDI parsing,please looking the WmEDISamples editoxml services which will show you convertToValues parsing snippet.
HTH,
RMG
#edi#Integration-Server-and-ESB#webMethods