Always use google 2fa authenticator to log in on exchanges.
And note, that when using Google 2FA, you should always back up the code used to enable it, so you can access your account if you lose the device in which the Authentication app is installed.
You can also preferably use Authy which stores your data in the cloud where you can always retrieve it
What if the codes were not saved somewhere else? Is there other way to recover or open the google 2fa with other device?