If you lose access to the phone you use to log in using 2FA, you can use recovery codes as an emergency solution to log in and turn off 2FA. You can only use recovery codes in the web app.
It's best to save your recovery codes on a device other than the one you use as an authenticator. That way, you can use the codes to log in if you lose your device.
Use recovery codes to login and turn off 2FA