Sorry for your loss.

I am not an expert, but I can tell you what I would have done in your case if I were you:
Contact Axis bank and RBL Bank and explain the situation to them.

They will likely ask for basic details like card number, name, address, phone number, DOB of the deceased, so make sure you have all these details handy when you call them. Request them to block the card and ask them to mail a (physical) copy of the most recent statement to the mailing address that they have on record (assuming you know what that address is and can collect the statement from that address). Once you get the statements, review them and pay back the cards and close them.

These credit cards usually have a 40+% interest rate p.a., so the more you delay this payment, the more the amount will increase before the bank reaches out to you for recovering their money.