@Dan Tsai
Thank you for your post!
Prior to accidentally deleting your account from the MS Authenticator app, if you backed up your account credentials you can easily Recover your account. If you'd like to go back to using your password for login:
For personal accounts, select the Use a password instead link during sign in. Your most recent choice is remembered and offered by default the next time you sign in. If you ever want to go back to using phone sign-in, select the Use an app instead link during sign in.
For work or school accounts, you must either unregister the device from the Settings page of the Microsoft Authenticator app, or disable the device from the Devices & activity area of your profile. For more information about disabling your device from your profile, see Update your profile and account info from the My Apps portal.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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