To change your bank account or card info open Branch, toggle to the "Access" tab (Dollar sign icon) and click the settings gear icon in the upper right hand corner of your Pay page. Then click the 3 dots next to the account you'd like to change and select "Update", you can make the updates to your card or bank account as needed.
If you're having trouble updating your bank account, reference this article: Why am I having trouble linking my bank account?
If you're having trouble updating your card, reference this article: Why is my card blocked?
If you're seeing an error message that says you've reached your maximum attempts to verify your accounts, please reach out to support here.