Last Updated: Dec 17, 2024
Overview
Passwordless SMS users are not receiving any text message with a code to enter.
Applies To
- Twilio
- SMS Authentication
- One Time Password (OTP)
Cause
This may be due to a misconfiguration on the Auth0 or Twilio side
Solution
In the tenant logs, the type: “cs” log type shows that login attempts are correctly triggering the Passwordless login code. Auth0 calls the Twilio API upon login, and if the API returns a 200 result, a log of type cs will be created.
After this, check to see if there is a failed login log and see what the error description is. If an incorrect Twilio SID or Twilio AuthToken is used in the Passwordless SMS settings, a user never gets an SMS message, and the tenant log records aType: Failed Login, Description: Failed to send sms notification error. Oftentimes, the error description will include an error code from Twilio that can be used to find the appropriate troubleshooting guide on their side. For example, the error description “Authenticate (Code: 20003)” comes from Twilio and has a troubleshooting guide here.
However, if there is a misconfiguration on the Twilio side and Twilio does not send back any errors to Auth0, there will not be an error message in a tenant log, and the next step would be to review the logs on the Twilio side.