Duplicate Supplier Name

Summary: System is not allowing to create a supplier with duplicate name.

Content (please ensure you mask any confidential information):

System is not allowing to create a supplier with duplicate name. Tax Payer ID and DUNS number is null for original Supplier. For new Supplier with same name as of original supplier, I am providing pax payer ID, Tax registration number and DUNS number. Still the system is throwing an error that Supplier name is duplicate, please enter unique supplier name.

From what I know is that, uniqueness of Suppliers is checked based on combination of Supplier name and tax payer ID / DUNS number.