POST /otp/resend

Advance the same OTP to the next enabled channel after a cooldown. The response has the same shape as send, with the new channel. Once your order is exhausted, a resend repeats the last usable channel rather than refusing. Pass an optional channel to move the OTP onto a specific channel instead of the next one: a fresh code is delivered there. You do not re-send client_ip: the resend is evaluated with the IP declared on the original send.

curl -X POST https://api.otp.com/api/v1/otp/resend \
  -H "Authorization: Bearer otp_live_•••" \
  -H "Content-Type: application/json" \
  -d '{"otp_id":"9f3c1b2a-…"}'

Request body

Field	Type	Required	Description
otp_id	string	yes	The id of the verification to advance.
channel	string	no	Move the OTP onto this exact channel (sms, whatsapp, telegram, email) instead of advancing to the next one. Must be enabled for your app and the recipient.

Verify by SMS when the user has no WhatsApp

In the two WhatsApp link modes the user has to open the action_url to finish, so a user without WhatsApp (or one whose code does not arrive) cannot complete it there. Resend with {"otp_id":"…","channel":"sms"} to move that pending OTP onto SMS: it delivers a fresh code and the response comes back with action_url: null, so you continue with the normal verify step. Naming the channel is what makes this work: a plain resend on an OTP that is already on a wa.me link just re-returns the same link. See WhatsApp verification.

Response

{
  "otp_id": "9f3c1b2a-…",
  "status": "pending",
  "channel": "whatsapp",
  "masked_recipient": "+1****71",
  "action_url": "https://wa.me/13845555555?text=Verify%20me%3A%20aB3xZ-…",
  "completion": "code"
}

channel reflects the next channel in your order. On SMS, email, and Telegram the same code is re-issued; a fresh code is not generated. WhatsApp under Template behaves the same way. In the two link modes a plain resend skips WhatsApp unless it is first in your order; name it with {"channel":"whatsapp"} to move the OTP onto it anyway, and the response returns an action_url for your app to show. A later plain resend re-returns that same link, so to move the OTP off WhatsApp, name the channel you want.

Common errors

Status	Type	When
409	ResendNotAllowedError	The OTP’s send attempts are spent, or no enabled channel is left for the recipient.
429	ResendCooldownError	Resend attempted within the cooldown window. Retry-After carries the seconds left.

See How verification works for the fallback model, or Error codes for the full list.