creditcard number check
Similar to the bank data, the credit card numbers also follow a very special algorithm.
(Luhn formula). Therefore, we can also clearly determine here whether it is a matter of formally and logically
credit card information is correct or not.
creditcard-amount check
For services that are billed on a time basis (e.g. online consultations), the exact invoice amount is displayed
only after the service has been rendered. In this case, you can query in advance whether the
exists and currently has sufficient cover.
