Hello Captum, how are you trying to change the card payment? Are you trying to do it in the app version or the web version? If you are trying in the web version, can you try clearing your cache and cookies to all time, close the browser down, reload it and log back in and try again and see if it will then let you save the new card. If you still have an issue please let us know. Here is an article to take a look at as well Manage billing, payment, and subscription info in QuickBooks Online.
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