# Decline Details
source: https://developer.mastercard.com/mastercard-send-person-to-person/documentation/response-error-codes/decline-details/index.md

If the POST API request `decline_details` query parameter is set to 'true' and the transaction is declined, a 201 response is returned with full transaction details. Otherwise, a 402 error response is returned (the default). GET 200 responses also include the full transaction details.

201 / 200 response messages for declined transactions may include either of these fields in the `transaction` array:

* `network_decision_code` = Network Decision Code, present when the transaction was declined by the Mastercard Network instead of the issuer.

* `merchant_advice_code` = Merchant Advice Code, present when the transaction was declined by the issuer.

The codes supplement the `network_status_code` (see [Network Response Codes](https://developer.mastercard.com/mastercard-send-person-to-person/documentation/response-error-codes/network-response-codes/index.md)) and can help you determine whether to retry a declined transaction.

## Network Decision Code {#network-decision-code}

The action taken by the Mastercard Network. Possible codes:

| Code |                                                                                Description                                                                                |
|------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| 00   | Mastercard on-behalf decision when primary authorization system or communication network of a payment network is unavailable or experiencing issues.                      |
| 01   | Mastercard processing decision or issuer not available. Can retry.                                                                                                        |
| 02   | Transaction declined because original transaction was not found. Only applicable to transactions processed as Single Message transactions, not Dual Message transactions. |
| 03   | Transaction declined by Mastercard because sanctions limit exceeded.                                                                                                      |

## Merchant Advice Code {#merchant-advice-code}

The action taken by the issuer or its advice to the merchant. Possible codes:

| Code |                     Description                      |
|------|------------------------------------------------------|
| 01   | New Account Information Available                    |
| 02   | Try Again Later                                      |
| 03   | Do Not Try Again                                     |
| 04   | Token requirements not fulfilled for this token type |
| 05   | Negotiated value not approved                        |
| 21   | Payment Cancellation                                 |
| 22   | Merchant does not qualify for product code           |
| 24   | Retry after 1 hour (Mastercard use only)             |
| 25   | Retry after 24 hours (Mastercard use only)           |
| 26   | Retry after 2 days (Mastercard use only)             |
| 27   | Retry after 4 days (Mastercard use only)             |
| 28   | Retry after 6 days (Mastercard use only)             |
| 29   | Retry after 8 days (Mastercard use only)             |
| 30   | Retry after 10 days (Mastercard use only)            |
| 40   | Consumer non-reloadable prepaid card                 |
| 41   | Consumer single-use virtual card number              |