If you can no longer get a 6-digit code from your authenticator app (a lost, wiped, or reset phone), you're not permanently locked out, resetting your password is also your recovery path here.
- Go to Forgot Password and reset your password as usual.
- Once you set a new password, you'll see an option right there to turn off two-factor authentication. This is available at that exact moment because you've just proven ownership of the account another way (control of the email address), so it's a reasonable point to also let you clear the second factor.
Once 2FA is off, you can sign in normally with just your new password. Set 2FA back up whenever you have a working authenticator app again, from Profile → Security.