Procedure of sending purchase rejection

Respected Experts

Please brief the procedure for returning rejected goods to the supplier. Currently we used to prepare a tax invoice for returing rejected goods to the supplier. But our vat auditor/consultant is insisting on raising debit notes instead of invoice.

Secondly if raise invoice to return back the goods to OMS supplier what is about C Form and should we pay the CST

And if we raise a tax invoice where should we show the transaction in Vat Return? In GTO Sales or GTO Purchase?

Your brief comments are needed urgently, as the issue has become very complicated.

Thanks in advance

Regards

Suhas Deshmukh