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WEBHOOK
card.negative_balance
{
  "event": "card.negative_balance",
  "version": "3.0",
  "eventId": "b4c5d6e7-f8a9-0123-7890-bcdef0123456",
  "sign": "a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0c1d2e3f4a5b6c7d8e9f0a1b2",
  "data": {
    "cardId": "a4e8f2b6c9d1e3f7a2b5c8d0e4f1a3b6c9d2e5f8a1b4c7d0e3",
    "cardholderId": "8f4e2a1b3c5d7e9f0a2b4c6d8e0f1a3b5c7d",
    "amount": 3.50,
    "currency": "USD",
    "appId": "A1B2C3D4E5F6G7H8",
    "timestamp": "2026-05-10T14:32:00Z"
  }
}

{}

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{
  "event": "card.negative_balance",
  "version": "3.0",
  "eventId": "b4c5d6e7-f8a9-0123-7890-bcdef0123456",
  "sign": "a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0c1d2e3f4a5b6c7d8e9f0a1b2",
  "data": {
    "cardId": "a4e8f2b6c9d1e3f7a2b5c8d0e4f1a3b6c9d2e5f8a1b4c7d0e3",
    "cardholderId": "8f4e2a1b3c5d7e9f0a2b4c6d8e0f1a3b5c7d",
    "amount": 3.50,
    "currency": "USD",
    "appId": "A1B2C3D4E5F6G7H8",
    "timestamp": "2026-05-10T14:32:00Z"
  }
}

{}

Body

application/json
​
event
string

The event type identifier (e.g. card.funded).

​
version
string

Webhook payload version.

​
sign
string

HMAC-SHA256 signature of the data object using your webhook secret. Always verify this before processing.

​
data
object

Response

200

Acknowledge receipt of the event