What this error message means
It looks like your debit card has already been used for a previous Dave account (whether it's active or not).
Most likely, you got a new phone number and this card is still associated with your old account.
What you can do to fix it
Please visit the Profile tab in-app and scroll to the bottom of the screen to find the Help Center.
Message Dave's support team and we'll help to get it sorted out for you.