Your card is the one piece of your relationship with stub that stub deliberately never touches. Card changes happen in stub's secure billing portal, which you reach from the app — so a new card, an expired one, or a failed payment is a two-minute fix, not a support ticket.
The usual reasons you'll be here: the bank reissued your card and the number changed, the old one expired and the debit bounced, or you're moving the subscription onto the business card instead of your personal one.
Update your card
Go to Settings → Billing and click Manage on your plan card. The secure billing portal opens — update your payment method there and come back to stub when you're done. There are no card fields in the app itself, because stub never stores or shows your card.
If a payment fails
Your plan card shows Overdue, and the notice at the top of Settings → Billing gives the date your account gets downgraded. Nothing is lost yet — you just need a working card in place before that date.
Click Update on the notice. stub takes you to its secure payment page — enter the working card there and confirm. Once the payment clears, everything switches back on.
Common causes: an expired card, a new card number after a bank reissue, or a bank blocking a recurring payment it doesn't recognise.
If your bank asks you to confirm
Your bank may ask you to approve the payment in its app, or by one-time PIN. Approve it and the payment completes.
If a partner manages your subscription
If your subscription came through a partner, clicking Manage tells you so. They hold the payment details — speak to them.
Check what you were charged
Your tax invoices are on the same page, so you can always see exactly what went off your card. See Download stub invoices.