Is the interest calculated on payment of challan/credit in ledger or filing of GSTR-3B?

For the quarter ending June, our payment of GST liability was credited in the electronic ledger by due date but there was a delay of 2 days in filing the GSTR-3B. This quarter's GSTR3B has a late fee of Rs 100 auto-filled but there also a checkbox ticked asking about any interest liabilities.

So do we also have to pay interest for 2 days apart from the late fee? I want to clarify again that the liability was paid through the challan by the due date, only return filing was delayed.

Thanks for your help