How can I find out who owns the business listed under a DBA?
That would very much depend on the jurisdiction (state, county and/or city) where the DBA is registered. Some jurisdictions have easily searchable online databases, while others still maintain their records in physical form.
(a) You made a typo in the card number, CCV code, expiration date, name or address;
(b) Your card balance is too low;
(c) Issuing bank has declined this transaction for some other reason related to your account.