GSTR-1 returns

You can not claim input tax

Certain conditions has to be fulfilled

To fulfill the requirements of a certain set of circumstances, it is essential to run 3

When a supplier files GSTR-1 returns late and incorrectly shows CGST+SGST instead of IGST (as reflected in GSTR 1), it can lead to discrepancies in GSTR 2A. Here are some steps you can take to address this situation:

Communication with Supplier:
Continue reaching out to the supplier and request them to rectify the invoices. Document all communication attempts.
Explain the issue clearly, emphasizing that the party paid taxes as CGST+SGST, but you need the correct IGST input.
Rectification of Invoices:
If the supplier responds, ask them to revise the invoices in their GSTR-1 to reflect the correct IGST.
The supplier should file an amendment to correct the error. They can do this by filing a revised GSTR-1 for the relevant tax period.
Claiming Correct Input Tax Credit (ITC):
Since the incorrect ITC is not reflecting in GSTR-2A, you can’t claim it directly.
Adjust the ITC in subsequent months’ GSTR-3B returns. If the adjustment isn’t feasible, you can claim a refund.
Legal Options:
If the supplier doesn’t cooperate, consider legal options such as sending a legal notice or seeking professional advice.
Consult a tax expert or a legal professional to explore further actions based on your specific situation.
Remember that timely communication and persistence are crucial. Keep records of all interactions with the supplier for future reference.