Payzapp QR Code transaction charges with funds in wallet

Tried to book tickets on IRCTC via Payzapp QR Scan. Fortunately, just had sufficient funds for the ticket. But the ticket did not go through. When contacted customer care, he said merchant is charging about extra 3% and I do not have enough funds in the wallet card.

Booked through linked card and there are no extra charges except 1.1% which is from irctc.

So beware while using the same.