Molten Shell animation does not show up and I miss my hits

My Molten Shell animation sometimes does not show up when I enable it.

Also I miss a lot of my hits with Flicker Strike even though I enabled Resolute Technique keystone.

These two problems seem like started to happening after a certain event. I accepted two party invitations almost at the same time so the game bugged out for a while and I stuck in a party with somebody. When I tried to leave that party, chat system said: "The party does not exist." so I exited the game but still no difference. After a while that party disappeared spontaneously (I entered to PvP, maybe that fixed) and then my miss of hits and Molten Shell animation problem started. I'm not sure they are relevant tough...



It also happens in PvE:



Addition:

That's exactly what's happening to me about missing hits with Flicker Strike:
https://www.youtube.com/watch?v=b-olAaaza4s

I read this post https://www.pathofexile.com/forum/view-thread/22551 and apparently I'm experiencing some sort of desynchronization on server-side. Please help me.