I was having this issue as well and went back and forth with the dev on that. What he worked out was that capitalization of the username was causing issues. I had to delete/re-add my accounts to rectify it.
I can login, was actually replying from Memmy to see if it got fixed. My other account loads the profile, but this one on this instance doesn’t for some reason, and while I like my blahaj.zone account, I figured it’d be nice to see some of the other stuff and choose for myself what I do or don’t want to see, hence the infosec.pub account that Memmy doesn’t show the profile for.
Though frankly, most of what I see on here that’s different is like exploding-heads garbage, so it’s not like I was really missing out on anything with blahaj.zone.