Dannii asked me to post this.
Apparently when you add someone to your block list in-game, and they change their name, the name on the block list is displayed as "Doesn't exist".
Once that happens, players can not remove that name any longer, and they can not see what the blocked user says.
Only admins can remove the invalid name manually from that point.
Please check,
Thank you.
It gives you that error if you try to block a staff
it give your an error if you try to block dannii.
Very interesting
I think blocking people is too much work. :/ Just insult them back if they're insulting you, there's no reason to be butthurt because somebody is being a jerk to you on the internet