Why can’t I turn off two factor authentication?

Use the link in the email received when you turned it on... unless you turned it on when you created your account, in which case you can't turn it off at all.

You're not talking to Apple. This is a user forum. We can't change it.

You can't turn it off after it has been enabled. If you enable it you have a 2 week period to turn it off. After that it is permanently enabled. Sorry.