I also already had 2FA enabled. Got the aforementioned notification and even a private message sent to my account about enabling something I already had. Was super confused, though thankfully the language conveyed it wasn’t some sort of account breach.
Hey! This issue should now be fixed. We should no longer be showing any messaging that implies that Authenticator isn’t already enabled on your account if you do have it enabled. We may at times show communications that reiterate the importance of keeping Authenticator enabled, and we will ensure that this messaging is clear. Thank you!