what is the merchant category of credit card bill payment site like CRED mobikwik paynet etc

i got DBS debit card and need to spend 3K in two transaction.. they dont allow wallet paymen t.. i was thinking of paying my credit card bil thru it
https://www.dbs.com/digibank/in/promotions/welc...
Spends only on shopping or at e-commerce merchants to be eligible for the offer. The following transactions are not considered eligible as part of this offer

Any transaction to fund a digibank or a RuPiZo account or any other wallet (e.g. PayTM, PayUMoney, Mobikik, Citrus, Airtel Money etc.) or savings account using digibank Debit Card (even if the wallet is refilled to make a purchase)
Cash withdrawals at ATMs or DBS Bank branches, fuel payment, tax payments, insurance or mutual fund purchase will not be considered as a spend for this offer
Fund transfers to other account
In-app transactions (Recharge, Bill Payment, QR Code Payment, UPI)
Online gaming websites
Incomplete / rejected / invalid / returned /disputed or unauthorized / fraudulent transactions will not be considered for the offer.