Muting Teammate Doesn't Work (Bug)

I'm going to try to reproduce this bug but I wanted to know if any other players are experiencing this right now. Last game I had a blitzcrank that was trolling me which was a long story but basically I muted him. But then I see his flipping messages still in team chat and I'm just thinking wt fudge riot are you kidding me right now. I muted unmuted mute unmute and I could still see little bltizy poos messages and bottom line I'm livid. I'll go in a game with friends and try to see if I can repoduce this bug and record. If I can reproduce it I'll make another thread and link it to my youtube. I don't upload very often but I should be recording my games for bull like this for future situations. I'm just curious if this is a random error or if others are having this as well.