I must add I found the 2FA a pain. 2 different authentication apps that I attempted to use offered me a 3 day free trial and my credit card number flashed up so I hope I'm not signed up for these as I can't see anywhere to unsubscribe.
Wait, that's weird.
That looks shady since 2FA apps don't even need to be connected to the internet to work and the legit ones do not require any subscription.
You may have something malicious in that phone that caused the subscription prompt if you're using any of the famously used authenticator apps during that attempt.
You may start a new topic if you wish to set-up 2FA,
But you must include the steps that you've used in your previous attempt and the apps that you've used.