it may have to do with the popular lemmy instances being slammed right now. Until very recently, they weren’t handling a lot of heavy traffic-- after Christian Selig’s initial announcement about the Reddit API changes, there was a massive spike in traffic from Reddexiters, and, now, again within the last hour since his latest post. Instance admins are expanding their capacity, but can only do so much, being independent volunteers running servers on their own.

Give it time. the servers are a bit bogged down right now.