You can login using an authentication code received using a pre-registered backup phone number in cases in which you have lost your mobile device, or cannot receive authentication code through your authentication application or SMS.
* This feature is not available with the free plan.

 

Setting up a backup phone number

1. From the menu under the [Username] in the top right of the chat screen, select Account Settings.
2. Click the [Change] button for two-factor authentication.
3. Click [Settings] for the backup phone number.
4. Enter your country code and phone number, and click [Send SMS].
5. Enter the six digit authentication code you received by SMS and click [Phone number validation].