Update your payment method
If you subscribed on the web, update your card from Subscription in Settings, where Manage Billing opens your Stripe billing portal. If you subscribed through Apple or Google, your payment method is managed in your App Store or Google Play account settings, not inside MailOver.
Web subscriptions (Stripe)
If you pay through Stripe on the web, you update your card in the Stripe billing portal.
Open Settings and go to Subscription. In the MailOver web app, open Settings, then the Subscription section.
Select Manage Billing. This opens your Stripe billing portal in a new tab, where your saved card and billing details live.
Add a new card or update the one on file, then save. Stripe stores your card details securely, MailOver never sees them. Close the tab when you are done.
Apple and Google subscriptions
If you subscribed inside the iOS or Android app, your payment method belongs to your Apple ID or your Google account, not to MailOver. You change the card in the store rather than in the app. On iPhone, open the Settings app, tap your name, then Payment & Shipping. On Android, open the Google Play Store, tap your profile, then Payments & subscriptions, then Payment methods.
Not sure which provider you are on? Open Settings, go to Subscription, and check the Payment line. See Where you're billed if you need a hand.