For Example, A Supplier has prepared an Invoice for Sale, but actually that transaction didn't materialise. He prepared the invoice at the end of Sept'18, but after preparing the invoice the buyer refuses to purchase the goods from the supplier during Oct'18. The Supplier reported the particular transaction in GSTR-1 as well as GSTR-3B and paid tax.
Now, the question is How to adjust the same - Whether that particular invoice can be cancelled? Or, the supplier needs to issue credit note for the same and treat it as Sales Return and accordingly report the same in the upcoming return?