Add reference to error property for fraud reson

Signed-off-by: joaobaptistanqda <[email protected]>

docs/flows/crypto-onramp.mdx

@@ -507,6 +507,8 @@ Triggered when a user's order has failed.
   - `id` UUID of the widget.
   - `name`: Name of the widget.
   - `flow`: Flow associated with the widget.
+- `error`: Indicates specific error information.
+  - `reason`: Indicates the reason for the error, possible values are `fraud`.
 
 :::note
 The values for `origin.paymentMethod.type` can be found using our [REST API](../rest-api.md), via the [payment methods endpoint](https://api.topperpay.com/payment-methods/crypto-onramp).
@@ -566,6 +568,9 @@ The values for `origin.paymentMethod.type` can be found using our [REST API](../
       "name": "ACME",
       "flow": "crypto_onramp"
     }
+    "error": {
+      "reason": "fraud"
+    }
     // highlight-end
   }
 }