Use the Auth0 Unlink a User Account endpoint or the Auth0.js library to unlink an identity from the target user account making it a separate user account again. The result of the unlinking process is the following:
  • The secondary account is removed from the identities array of the primary account.
  • A new secondary user account is created.
  • The secondary account will have no metadata.
If your goal is to delete the secondary identity entirely, you must first unlink the accounts, and then delete the newly created secondary account. Depending on from where you call the endpoint, use one of these two scopes: The endpoint uses the following parameters:
ParameterTypeDescription
idstringID of the primary user account (required)
providerstringidentity provider name of the secondary linked account (e.g. google-oauth2)
user_idstringID of the secondary linked account (e.g. 123456789081523216417 part after the `
If your instance has users from multiple providers, you may also include [connection_name]| before the user_id stringto name the provider (for example, "user-id": "google-oauth2|123456789081523216417").

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Response example

[
  {
    "connection": "Initial-Connection",
    "user_id": "5457edea1b8f22891a000004",
    "provider": "auth0",
    "isSocial": false,
    "access_token": "",
    "profileData": {
      "email": "",
      "email_verified": false,
      "name": "",
      "username": "johndoe",
      "given_name": "",
      "phone_number": "",
      "phone_verified": false,
      "family_name": ""
    }
  }
]

​
Use JWT from the primary account

To unlink accounts, call the Management API Unlink a User Account endpoint using the from the primary account for authorization: 
function unlinkAccount(secondaryProvider, secondaryUserId){
  var primaryUserId = localStorage.getItem('user_id');
  var primaryJWT = localStorage.getItem('id_token');
  $.ajax({
    type: 'DELETE',
    url: 'https://' + '{yourDomain}' + '/api/v2/users/' + primaryUserId +
         '/identities/' + secondaryProvider + '/' + secondaryUserId,
    headers: {
      'Authorization': 'Bearer ' + primaryJWT
    }
  }).then(function(identities){
    alert('unlinked!');
    showLinkedAccounts(identities);
  }).fail(function(jqXHR){
    alert('Error unlinking Accounts: ' + jqXHR.status + ' ' + jqXHR.responseText);
  });
}

​
Use Access Token with the update:users scope

If you need to unlink two or more user accounts, call the Management API Unlink a User Account endpoint using an Management API Access Token with the update:users scope. 
function unlinkAccount(secondaryProvider, secondaryUserId) {
  var primaryUserId = localStorage.getItem('user_id');
  var primaryAccessToken = localStorage.getItem('access_token');

  // Uses the Access Token of the primary user as a bearer token to identify the account
  // which will have the account unlinked to, and the user id of the secondary user, to identify
  // the user that will be unlinked from the primary account.

  $.ajax({
    type: 'DELETE',
    url: 'https://' + AUTH0_DOMAIN +'/api/v2/users/' + primaryUserId +
         '/identities/' + secondaryProvider + '/' + secondaryUserId,
    headers: {
      'Authorization': 'Bearer ' + primaryAccessToken
    }
  }).then(function(identities){
    alert('unlinked!');
    showLinkedAccounts(identities);
  }).fail(function(jqXHR){
    alert('Error unlinking Accounts: ' + jqXHR.status + ' ' + jqXHR.responseText);
  });
}
  1. Update the user in session with the new array of identities (each of which represent a separate user account).
const ensureLoggedIn = require('connect-ensure-login').ensureLoggedIn();
const Auth0Client = require('../Auth0Client');
const express = require('express');
const router = express.Router();
...
router.post('/unlink-accounts/:targetUserProvider/:targetUserId',ensureLoggedIn, (req,res,next) => {
  Auth0Client.unlinkAccounts(req.user.id, req.params.targetUserProvider, req.params.targetUserId)
  .then( identities => {
    req.user.identities = req.user._json.identities = identities;
    res.send(identities);
  })
  .catch( err => {
    console.log('Error unlinking accounts!',err);
    next(err);
  });
});
  1. Call the Management API v2 Unlink a User Account endpoint using an Management API Access Token with the update:users scope.
const request = require('request');

class Auth0Client {
  ...
  unlinkAccounts(rootUserId, targetUserProvider, targetUserId){
    return new Promise((resolve,reject) => {
      var reqOpts = {
        method: 'DELETE',
        url: 'https://{yourDomain}/api/v2/users/' + rootUserId +
            '/identities/' + targetUserProvider + '/' + targetUserId,
        headers: {
          'Authorization': 'Bearer ' + process.env.AUTH0_APIV2_TOKEN
        }
      };
      request(reqOpts,(error, response, body) => {
        if (error) {
          return reject(error);
        } else if (response.statusCode !== 200) {
          return reject('Error unlinking accounts. Status: '+ response.statusCode + ' ' + JSON.stringify(body));
        } else {
          resolve(JSON.parse(body));
        }
      });
    });
  }
}

module.exports = new Auth0Client();

​
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