It is really important to backup your connected accounts so that you can recover access in the event you lose, damage or replace your phone.  


https://help.salesforce.com/s/articleView?id=sf.salesforce_authenticator_backup.htm&type=5


The text below is from the above link (March 23)- clink on the link for the most up to date advice


You can back up your Connected Accounts in the Salesforce Authenticator mobile app. If you lose, damage, or replace your mobile device, you can restore your Connected Accounts on another mobile device.

The back up and restore feature is available if you have a Salesforce account connected to the app. To use the feature and avoid disruptions, ensure you have at least one Salesforce account connected.

You can enable backups in these ways:

  • Tap the Notifications icon (Salesforce Authenticator notification pane icon) in the upper right corner, then tap Enable Backups.
  • If you don't see a notification, tap the Settings icon (Salesforce Authenticator settings page icon) in the upper left corner, then tap Back up accounts.

After you enable backups, complete the backup process by verifying your mobile number and setting a four-digit passcode.

  1. When prompted, enter your mobile number and tap Send.
  2. Salesforce Authenticator sends you a text message with a link. Tap the link in the text message.
  3. Authorize your mobile device to open the Salesforce Authenticator mobile app. This process is different on Android and iOS devices.
    • For Android, if prompted to select which app to open the link with, tap Salesforce Authenticator from the list. If your web browser opens, tap Open Salesforce Authenticator.
    • For iOS, when asked for permission to open Salesforce Authenticator, tap Open to approve.
    The Salesforce Authenticator app opens, completing the mobile number verification process.
  4. Set your four-digit or longer passcode. This passcode lets you restore your accounts on a new device.

To change or update your mobile number, in the Settings menu, tap Verified number. Enter a new mobile number and repeat the verification process.

To change your passcode, in the Settings menu, tap Change backup passcode. Enter a new passcode.