So is this about unblocking people?
Blocking isn't working?

You can still be paired with blocked players in 4pc
why??
then what is the use of block option?
I know a guy in 2 player giveaway chess. I used to farm him a lot. Then he blocked me. Now I can see his queue in lobby but whenever I try to join it says "Sorry player has blocked you".

blocking doesn't work for anonymous. it only works for semi anon and normal non anonymous games.
Then anonymous should also be included in it. We don't ban people only because of personal issues. We also ban for playing styles. I know someone is a bad opposite so I block him but next day again he betrays me what is use of block option here?
Because we have a small player pool and some players would probably block half the server if blocking worked in anonymous.
Yesterday I blocked 2 players and today both of them got paired to me in the same game in Standard anonymous FFA 2400+. This is really strange.