Does NOT Match (N)
Is NOT Processed (P)
Should be on card, but is not indicated (S)
Issuer is not certified or has not provided encryption key (U)
WHich ones should I check?
I have the CCV code as a required field and would like to make sure that the CCV is used. SHould I check all, then it has to match to be approved?
The primary filter for Card Code is the "N" for "Does NOT Match". This is the response that will be returned whenever a card code is entered by the customer and the card issuing bank confirms that it is invalid. The rest of the filters are far less common and are not returned due to the fault of the cardholder.
The "P" filter for "Is NOT Processed" indicates that the the customer entered the card code, but for some reason either your card processor or the customer's bank did not provide a response.
The remaining two filters of S and U both indicate some sort of misconfiguration at the issuing bank. Both of these responses are now exceedingly uncommon as banks are required by Visa and Mastercard to support card code verification.