"...not a valid, SMS-capable inbound phone number... (Code: 21606)", "errorCode":"auth0_idp_error"

Hello Auth0,

I am trying to create a single test user via sms connection, using the management API (node.js).

My fixture looks like this:

const userFixture = {
  connection: 'sms',
  name: 'John Doe',
  phone_number: '+61xxxxxxxxx',
  app_metadata: {
    access: 'MEMBER',

And I get:

"The From phone number +15005550006 is not a valid, SMS-capable 
inbound phone number or short code for your account. (Code: 
21606)", "errorCode":"auth0_idp_error"

I understand this is the default phone number for Twilio, to be used with test accounts. I am probably using a “live” Auth0 API, although it is currently used exclusively for testing.

Operations using other connections work just fine, but not this one.

What am I doing wrong, and more importantly - how can I resolve that?

Hi @argo and welcome to the Auth0 Community! :tada:

When you configured your passwordless SMS connection in the Auth0 Dashboard, where did you get the ‘From’ phone number (+15005550006)? Is that the ‘Trial Number’ that shows up in your Twilio Dashboard (screenshot attached)?

When I configured this connection and used the Management API to create a Passwordless SMS user, it seemed to all work as expected. The object I used to create this user was like so:

“phone_number”: “+1XXXXXXXXXX”,
“name”: “John Doe”,
“app_metadata”: {

Hope this helps, let me know what further questions you might have.

Best Regards,

Thanks Colin. I think someone on the team changed that configuration, which doesn’t seem accessible to me. It is likely simple as that. We will look into it.

Appreciate the help.

So, I finally got round to configuring this.

The number is the “magic number” mentioned here:

Simulate a successful message by sending an SMS using the magic number +15005550006 as the From number, and a regular phone number for the To number.

As it is a test number, I have to believe it is not SMS-capable for inbound messages.

Kindly note that I am able to create users, but if using the test number above, I get this error or warning anyway.