So if you have enabled 2fa on your Microsoft account and then enabled Microsoft Authenticator and you uninstall the authenticator app, you can no longer login to your email account.
You cannot ask for help as that requires you to login. You can basically do nothing.
When you login to your Microsoft account, you enter your password, then the login page prompts you to accept the login on the Authenticator app. Without the app, if you try and login using your backup email or phone number, you are routed back to your enter password screen. This then loops endlessly.
I have written to Microsoft regarding this. Let me see if they reply. Will update the post soon hopefully.