What is the difference between Discover codes NA and DA?

NA covers transactions settled with no valid authorization at all, while declined-authorization disputes address sales completed after the network said no. In practice both come back to the same discipline: never settle anything lacking a live approval code for the full amount.

My gateway shows an approval but Discover says there is no authorization. Who is right?

Pull the raw authorization response from your gateway logs, including the approval code and network reference. Mismatches sometimes trace to a sandbox flag, a different card network routing, or an authorization voided before capture. Submit whatever approval evidence you have; if the network reference does not exist on Discover's side, investigate your routing configuration.

Can I capture more than I authorized if the order total changed?

Not safely. Settling above the approved amount invites an NA or altered-amount dispute for the excess. Void and re-authorize for the new total, or run an incremental authorization where supported, before capturing the higher amount.

Discover · Authorization

Reason code NA: No Authorization

The merchant settled a transaction without obtaining a valid authorization approval from Discover. Either no authorization request was ever made, the request was declined and the sale processed anyway, or the settled amount exceeded what was approved. The transaction bypassed the control that lets Discover manage account risk in real time.

Issuer filing window

typically 120 days from the processing date

Merchant response window

typically 30 days to respond

Why NA chargebacks happen

A declined authorization was force-captured to save the sale.
Store-and-forward or offline terminal modes completed sales that never received online approval.
The settlement amount was inflated above the authorized amount beyond any allowed tolerance.
An integration defect settled captures whose authorization requests had errored out.
An authorization expired before capture and the merchant settled against the dead approval.

How to fight a NA chargeback

Locate and submit the authorization approval code with its date, amount, and response data if one exists; a valid approval defeats the dispute outright.
If the capture exceeded the authorized amount, defend the authorized portion with the approval record and concede or refund the excess.
Show that any incremental or delayed capture followed a valid original authorization under stored-credential rules, with the transaction IDs linking them.
Provide gateway logs proving the authorization request and approval if your acquirer's records are incomplete.
If no approval was ever obtained, do not represent; an unauthorized settlement has no defense and the fee is wasted.

How to prevent NA chargebacks

Configure your stack so settlement is mechanically impossible without a stored approval code for the full captured amount.
Remove force-capture and offline sale capability everywhere; in card-not-present commerce there is no legitimate use for them.
Capture within the authorization's validity period and re-authorize when fulfillment delays exceed it.
Alert on any capture-to-authorization mismatch in amount or transaction ID before batch submission.
Audit gateway retry logic so declined attempts can never fall through to capture.

Frequently asked questions

What is the difference between Discover codes NA and DA?: NA covers transactions settled with no valid authorization at all, while declined-authorization disputes address sales completed after the network said no. In practice both come back to the same discipline: never settle anything lacking a live approval code for the full amount.
My gateway shows an approval but Discover says there is no authorization. Who is right?: Pull the raw authorization response from your gateway logs, including the approval code and network reference. Mismatches sometimes trace to a sandbox flag, a different card network routing, or an authorization voided before capture. Submit whatever approval evidence you have; if the network reference does not exist on Discover's side, investigate your routing configuration.
Can I capture more than I authorized if the order total changed?: Not safely. Settling above the approved amount invites an NA or altered-amount dispute for the excess. Void and re-authorize for the new total, or run an incremental authorization where supported, before capturing the higher amount.

Related Discover codes