SAP Message BBP_CT_SLS300 - An import reference already exists for BP &1 and product category

Diagnosis
You want to select a product as import reference for business partnerV1. an import reference product already exists for this businesspartner in the product category &v2& (to which the selected productalso belongs). Only one product can be maintained as import referencefor each business partner and product category.

System Response
The system cannot create the "Import reference product for BP"relationship.