Diagnosis
Distributor's partner is reported as &SYST-MSGV1&. However, in theexternal to internal partner mapping (transaction /SAPHT/DRM_C10) nointernal partner has been maintained for external partner &SYST-MSGV1&and tracking partner &SYST-MSGV2&. The distributor did not report anyinternal partner.

Procedure
Create an internal partner (customer master) which will get updated inthe external to internal partner mapping. The newly created internalpartner will also be updated in staging records with internal partnerblank, Distributor's partner as &SYST-MSGV1& and tracking partnerSyst-msgv2.
OR
Search for existing internal partners (customer master) based onaddress. The selected internal partner will get updated in theexternal to internal partner mapping and staging records with internalpartner blank, Distributor's partner as &SYST-MSGV1& and trackingpartner &SYST-MSGV2&.