It seems it has been resolved, I was able to log in normally yesterday.

I just watched a stream, and the streamer also had exactly the same error.
Seems a lot of people are experiencing this issue at the moment.

Ok, what I did, and it resolved itself yesterday, I had to give the server time to restart.
I still don't know what caused it, or how it resolved it.
I suspect it is a problem with the main server database, and the data for my character got corrupted.
It is happening again.