Duplicate Validation Level in Manage Country default

Summary:

Want to enable the duplicate validation level to ONLY SUPPLIERS. In other words i should NOT be able to create 2 suppliers with the same tax registration numbers
This validation is not required at customer level or across supplier and customer records

Content (please ensure you mask any confidential information):

Want to enable the duplicate validation level to ONLY SUPPLIERS. In other words i should NOT be able to create 2 suppliers with the same tax registration numbers
This validation is not required at customer level or across supplier and customer records

Even if i set the Duplicate Validation Level to Suppliers or Same part type etc and Validation level is Error, it still validates if the tax registration exists in a customer record or any other party type