---
title: "Trigger SMS Challenge"
method: POST
path: "/v1/one-time-token/sms/trigger"
tags: ["sca-otp"]
---

# Trigger SMS Challenge

`POST /v1/one-time-token/sms/trigger`

To trigger a SMS challenge by sending SMS to user verified [phone number](/api-reference/user-security/usersecurityphonenumberlist) containing a 6 digit one time password (**OTP**).

This **OTP** code can be used to clear a SMS challenge by using the [Verify SMS endpoint](/api-reference/sca-otp/ottsmsverify).

## Headers

- `One-Time-Token` string, required
- `X-External-Correlation-Id` string, uuid

## Response `200`

Trigger result with obfuscated phone number.

- object
  - `obfuscatedPhoneNo` string — Obfuscated phone number that can be used as a hint for the end customer regarding which phone number the SMS was sent to.

## Other responses

- `429` — Rate limit exceeded. Retry after the number of seconds specified in the `Retry-After` header.

---

[API](https://skmtc.net/wise/apis/platform-api.md) · [All operations](https://skmtc.net/wise/apis/platform-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/wise/platform-api/revisions/4907a1d269ab/schema)