Message SAP WVMI202 - Vendor material &2 from vendor &1 not unique

Diagnosis
Only the material number for the vendor was entered for a material inthe IDoc. This material number is contained in several purchasing inforecords and cannot therefore be used to determine a material.

System Response
IDoc inbound processing has been terminated.

Procedure
Change the relevant purchasing info records so that the vendor materialnumber is uniquely assigned to exactly one material number, or ask thevendor to use your material numbers.