Flaw in registration form

Apparently I registered for this forum  at some time in the past, though I don't remember doing so. But because the system has my email address (which, it implies, is in use by someone else, which is impossible), I can neither log in nor register with my actual email. So I used an email address that I have only because I use an Android phone. It may be that this registration form was designed before someone invented the "forgot password" and "forgot user name" escape hatches (which, I'd guess, occurred in about 1997). Can this gap be closed?