Your post isn't really clear.
What exactly are you trying to do?
If you try to buy membership/add-ons/cash credit with Revolut or any other payment option and it fails then it's not going to try again unilaterally. You'll have to try again manually.
If a membership auto-renewal payment fails then it's not going to be attempted again until another month has passed as far as I know. So if it fails and you still need a membership plan then you'll almost certainly have to buy it manually for that month.
If you need to contact 48 support about this then see the link in my signature below or email them at support@48months.zendesk.com
