How do I change the saved card?

To change the saved card, open Plan & billing → the "Payment details" section. Next to "Card on file", tap "Update card". It re-opens the same "Add your card" authorization (your plan's fixed monthly price, 0% commission) and sends you to the bank's secure page to enter the new card. The new card replaces the old one and becomes the card charged each month. One thing: there is no separate "remove card" button — updating means entering a fresh card through the bank, and you re-confirm the authorization each time.