Missing or incorrect billing information is the number one reason a transaction may decline as "Surcharge Not Supported". Please make sure that the customer's profile has a full billing information listed and matches to the payment method being used.
Additional reasons why the charge might decline as Surcharge Not Supported :
Surcharges cannot be applied to transactions when the cardholder is paying with a Signature Debit, PIN Debit, PINless Debit, or Prepaid card. For these payment types, the surcharge will not be applied.
Surcharges cannot be applied to card-not-present e-commerce, mail, telephone, and recurring transactions when the cardholder's postal code matches a restricted region. For these transactions, the merchant must provide the cardholder's postal code to validate the cardholder's eligibility. If the postal code matches a restricted region, the surcharge will not be applied.
The Surcharge Rate of 3% of the post-tax amount of the transaction will be applied by the CardPointe Gateway.
The Surcharge Rate cannot vary at the transaction level. The Surcharge Rate of 3% is set for the merchant account, and automatically applied to applicable transactions.
The Surcharge Rate cannot be applied to partial authorizations. Partial authorizations are automatically disabled on surcharge-eligible transactions.
For additional insight (also, this was in everything she signed - the program guide has these details): here are the states it isn't allowed