---
title: "Unblock a card PIN"
method: POST
path: "/cards/{id}/pin/unblock"
tags: ["Cards"]
---

# Unblock a card PIN

`POST /cards/{id}/pin/unblock`

## Request

- Base URL: `https://api.lightspark.com/grid/2025-10-13`
- URL: `https://api.lightspark.com/grid/2025-10-13/cards/{id}/pin/unblock`
- Auth: HTTP basic

Clear a `BLOCKED` PIN, restoring the cardholder's existing PIN without changing it. A PIN blocks after three consecutive incorrect entries; until it is cleared, PIN-verified transactions decline.

Unblocking is idempotent and safe to call on a card whose `pinStatus` is already `OK`. It has no effect on a card with no PIN set, which returns `409` — set a PIN with `POST /cards/{id}/set-pin` instead.

Each card permits one unblock attempt per rolling seven days. Further attempts return `409 PIN_CHANGE_REQUIRED` with `details.pinUnblockAvailableAt`. Change the PIN through either PIN-entry flow to recover sooner; changing the PIN does not reset the unblock allowance.

Only request an unblock after authenticating the cardholder and receiving their explicit request. Do not automatically unblock after a declined transaction.

Grid supports online PINs only. Offline PIN cards are not supported. Read `GET /cards/{id}` to check `pinStatus`.

Every call is audit-logged with the requesting actor.

## Response `204`

PIN unblock accepted; read GET /cards/{id} for its `pinStatus`.

## Other responses

- `401`: Unauthorized
- `403`: Forbidden. The session has no attributable actor to audit the change against (for example, an impersonated dashboard session).
- `404`: Card not found
- `409`: Conflict. Returned with `CONFLICT` for a closed card, a card with no PIN to unblock, or a card that does not support PIN management. Returned with `PIN_CHANGE_REQUIRED` when the card's seven-day unblock allowance is consumed. Change the PIN or wait until `details.pinUnblockAvailableAt`.
- `500`: Internal service error
- `501`: Not implemented in this environment. Cards are not enabled for every Grid deployment; environments without card support return `501 NOT_IMPLEMENTED`.

## Changes

> 115 revisions in range; 2 not diffed.

- **2026-10-28** `d996ddfb9d2b`: 3 info
  - added the optional property `details/permission` to the response with the `403` status
  - added the optional property `details/policyDenialReason` to the response with the `403` status
  - added the optional property `details/refusalReason` to the response with the `403` status
- **2026-10-28** `5abf2bb56bcb`: 1 warning
  - added the new `CORRIDOR_UNDER_MAINTENANCE` enum value to the `code` response property for the response status `403`
- **2026-10-26** `f11f1e76bdd7`: 1 warning
  - added the new `PURCHASE_CARD_LIMIT_REACHED` enum value to the `code` response property for the response status `409`
- **2026-10-26** `0a6dad5815c7`: 1 warning
  - added the new `INVOICE_ALREADY_USED` enum value to the `code` response property for the response status `409`
- **2026-10-20** `761d1d030cb5`: 1 warning
  - added the new `AGENT_CARD_EXISTS` enum value to the `code` response property for the response status `409`

[Operation history](https://skmtc.dev/lightsparkdev/apis/grid-api/changes/cards/:id/pin/unblock/post.md)

---

[API](https://skmtc.dev/lightsparkdev/apis/grid-api.md) - [All operations](https://skmtc.dev/lightsparkdev/apis/grid-api/llms.txt) - [OpenAPI document](https://skmtc.dev/lightsparkdev/apis/grid-api/revisions/7a1db46ec552?raw)