There are several improvements you should make to your billing configuration in AWS to simplify and increase resiliency: Turn on Consolidated Billing to simplify billing into a single invoice.
While AWS gives you 90 days to resolve payment issues, those can still cause a lot of effort and stress to fix.
A credit card is the default payment method when you create an AWS account, but credit cards are risky because the card expires or can have insufficient funds. Your primary payment method should prefearbly be a bank account for SEPA