How do we Remove payment method

Did you already have a look at these related articles, to make sure that your payment information is complete and correct?

If you need to change or update your Apple ID payment method - Apple Support

If you have ongoing subscriptions, you will have to add a new payment method first, before you can remove the old one.

Go to your settings and then go to wallet and Apple Pay… then you can change your payment method….

Roblox appears to be a game platform with artificial consumables ("Robux") that you pay for with real money (in-app purchases).

https://apps.apple.com/us/app/roblox/id431946152