SAP Message WS756 - No default plant could be determined

Diagnosis
The system attempted to determine a default plant for the agencydocument data. However, no default plant was defined.
The system determines the default plant according to the following logic(in each case, provided the required key fields exist):
Customer material info (sales organization / sales area / invoicerecipient)
Supplying plant (invoice recipient / material group / valid for documentdate)
Sales data (sales organization / distribution channel / division /invoice recipient)
Sales data for material (material / sales organization / distributionchannel)
Plant for company code (table TMZWK) (companycode)

Procedure
The plant must be entered manually.