That’s why you should always, always, always save the recovery codes generated when you enable TOTP based 2FA.It isn't much better with being stuck with only being able to have codes active in one app. If Authy, OTP Auth, or another 2FA app goes down and you use that app, it makes life very messy. It would be nice to be able to have codes loaded in 2 different apps to help prevent a bad scenario.
If you use something like 1Password, you can save them there (something you still can’t do in Apple’s anemic password management). You can also take a screen cap of the QR code (or save the text string) and re-seed 2FA apps at a later date, although this doesn’t always work as some sites also cycle those codes.