For stupid reasons, I think my bank trying to protect me, they declined the charge for the adwords bill.
It costed my account being pause until I corrected it by entering my old working credit card.
It would be all this avoided if, like PayPal, they allowed to have multiple or backup credit cards associated with your account.
I can imagine of other problems related to this happening to others. I can't think a reason of why adwords billing is so primitive.