Arpit, it isnt clear as whom you called for the refund. If the Paytym has been approved and SBI amount hasn't been refunded yet, you will have to take a note of the transaction Id and get in touch with the Bank. NTA has nothing to do with this because the bank has failed to process the transaction.

Hi,

Well there are two things that might have happened. One that they themselves accepted the two time payment and the other one where the bank made the payment but it didn't reach the other side. In the first case, if they are saying then they will refund the money so you don't have to worry about it. And in the second case the bank will automatically refund the money. Just keep your transaction ID and merchant slip ready in order to show as proof. And if they have said then they will surely refund. Just have patience and wait for a bit.

I hope my answer helps.

All the best.