Coming back to Folding after a long hiatus. The login expects an email address. My stored credentials just has a username. How do I get around this?

It's been 7ish years since I used F@H and now I can't log in. I don't remember providing an email address to F@H, but I tried every email address I've ever had and none of them is showing as registered. I used to log in with a username but that isn't possible anymore, apparently. Any thoughts on what I can do to log in?