Diagnosis
The supplier may only operate as a partner for other suppliers (e.g. as ordering address or invoicing party), not as the supplier who actually fulfills the order.
Procedure
If this is a warning message, you can ignore it.
If this is an error message add partner role VN to the supplier master record: Perform function
SOLUTION:
STEP 1: Follow the below Path to configure : SPRO > IMG > Materials Management > Purchasing > Partner Determination > Partner Settings in Supplier Master Record > Assign Partner Schemas to Account Groups
STEP 2 : Position your Account Group and assign Supplier Partner Schema > SAVE
Thanks,
Adharsh K S