I was actually just about to make a post about this but I see you beat me to it. I posted about this on the piefed help community and I got this response from one of the Piefed devs:

Thanks for bringing this to my attention. There have been a couple of other similar cases in the last few days, so a pattern is forming.

There’s nothing you can do. Possibly creating a new account would solve it, if my theory about the root cause is correct. Some accounts may have corrupted data that got federated to other instances and now those instances are confused about the validity of your account. This should solve itself over time as caches expire and get refreshed but it’s been 3 days now so they should have by now. Perhaps my theory is wrong.

Anyway I’m monitoring the situation and will be doing more tests as time permits.

I noticed some of my comments even on that post were not federating, and another piefed.ca user there commented saying they were having similar issues, but thar comment wasn’t visible when I viewed it from my lemmy.ca account.

Glad this wasn’t just me. Noticing edits sometimes help make things federate, but things haven’t been working yet on my end as of yet.

Hmmm, I applied the latest updates a couple days ago but not seeing any errors in the logs. I just pulled in the latest changes yet again in case there was a fix, but I’ll dig more later today.

Noticed the same thing :(

Yes! Having the same problem for the last few days. I’ve been having to switch to another account. I’m not complaining though! It’s no biggie to go to piefed.social lol

Thanks for letting us know, we updated piefed the other day and that’s likely the cause. We’ll look into it!