Today Amazon blocked my account saying "unable to charge" and our "charge method is invalid"

The credit card is valid and confirmed valid by the card provider. The address/info etc... is all correct and hasn't changed.

Yet, We're now blocked out of seller central and and payments on hold.

Seller central don't understand the issue and give the usual BS 'I will escalate to the internal team'

Does ANYONE have a solution to this problem? Any help appreciated!