Formerly linked account unlinked. Endless loop.

When I log into my ATT account I am told that "This ID has limited options since there aren't any accounts linked to it" and I'm provided a link to "link your account(s)" . Never mind that I had waded through ATT's byzantine linking procedure three-years ago, none of that matters now.

So I obediently attempt to link my accounts by clicking on the "Link" link. After a cheery hourglass screen telling me to "Hang tight, we're almost there!" I come to the "Link an Account" screen which asks me for my phone number or account number, which I provide. "Hang tight, we're almost there!" appears again and the next screen tells me "Account Registered: Looks like the Person whose name is on the bill already created a userID".  I am presented with several options, none of which really addresses this quandary. The only remotely useful option is "My name is on the bill. I want to log in" but the reason I'm at this screen is because I had logged into my account and wanted to link accounts. But with no other workable option, I choose this and log in to my account once again to find (predictably) that I have a limited account and need to link accounts. An endless loop, no resolution possible.