Contract of Carriage got updated a few days go, this vague reason might be it:
https://www.flyfrontier.com/legal/co...ge?mobile=true
direct link to PDF:
https://f9prodcdn.azureedge.net/medi...c16jan2026.pdf
20 — Currency and Mode of Payment and Fees
B. All amounts due to Frontier must be paid with a credit or debit card; Frontier may require that each
passenger have a card on file with Frontier to purchase a ticket and complete transport on Frontier.
D. A service charge will apply to any improper chargeback on a credit or debit card and may be charged
to the same card via which the chargeback is made.
Not the same as the names on the tickets must match the credit card name but maybe possibly vague on purpose?
And I'd bet they get a lot of chargebacks on the second charge of bag fees that people end up having to pay at the airport. Probably have to start taking fraud stuff more seriously.