If you wish to change your mobile device or authenticator app used for 2FA, you may do so by following these steps:
Step 1: Go to the dropdown top right hand corner which contains your name, and click on your profile.
Step 2: Click on “Security Settings” tab and “Set Up 2FA” button
Step 3: Set up using your new device or authenticator app and fill in all the fields
Step 4: After that, click the save button.