Hi @tashi.wangdi,
The “SMS is not supported by landline phone number” error seems to come from Twilio’s Verify API and not Auth0.
After reviewing their docs here, I noticed that there is an option to disable validating phone numbers using the Twilio API settings SkipSmsToLandlines on your Verification Service to `false.
That setting would be located in your send-phone-message Hook, where you initialize client.verify.services. If you think the phone number is valid and should work, contact Twilio support.
Thanks,
Rueben