Mastercard Reason Code 4807

The card used appears on Mastercard's warning bulletin of cards reported lost, stolen, or restricted.

A card-present transaction was completed using a card that appears on Mastercard's shared warning list, usually meaning it was compromised.

Almost entirely a card-present, in-person issue — rare for pure online storefronts.

Terminal authorization log showing the warning bulletin wasn't flagged at time of sale, if applicable.

Not checking current warning-bulletin status for high-value in-person transactions.