An authorisation/payment may fail for several reasons:
Payment method has expired.
Insufficient funds or credit.
Security check wasn’t completed in time, or authorisation code was entered incorrectly.
Payment method is not approved for online transactions.
Payment method exceeded daily/monthly limit.
Unusual spending triggered bank security block.
If your payment is declined, your order isn't sent to the restaurant, and you aren't charged. Some banks may show an authorization hold even for a declined payment. It may take a few days for your card issuer to make the funds available again. If the hold is still there after several days, contact your bank or card issuer for help.
Once you resolve the issue with your payment method or add another one, you can place the order again.