CMA
13117 Points
Joined May 2009
1) Debit notes raised by you cannot be uploaded as part of GSTR1. If you have already done that, you can reverse the entry when you file GSTR1 for the subsequent tax period.
2) Also ask your vendor to raise a credit note (in respect of the debit note) and upload the same.
3) As far as GSTR3B is concerned, you are required to reverse the input tax credit to the extent of debit note (by manually reducing the ITC). Once the vendor uploads the credit note, ITC mismatch will be taken care of.