Transactions may be declined for a variety of reasons. Some of those reasons may include payment network limitations, incorrect information input during the transaction, or reaching your credit limit.
If a transaction has been declined, you may wish to check your balance to ensure you have available credit; if you do, you can try the transaction again. You may also wish to double-check that you entered the correct card number, expiration date, and security code when you were attempting the transaction.
If you are still experiencing difficulties, please contact Cardless Customer Support.