Kicked Player(s) Still Showing Up

Hello, I'm posting because I've used the Kick Player feature multiple times over the last few months to try and remove someone from our campaign (Tim) who we had issues with and no longer feel comfortable playing with. However, this individual is still showing up on the player's list. I've also tried removing an old player who no longer wanted to be part of the campaign, Anthony. Same issue. Is there any way to remove them permanently? Is this a bug? Thank you in advance. Any help is appreciated!

Are you the Creator of the game, or are you just a secondary GM? I was secondary GM for a large game and I could never Kick a player. Once I became the Creator I could Kick a player correctly. 

Ah, that makes sense. I am a secondary DM technically who is now the head DM for our group. That might be it. I'll see if I can message our old DM and ask him to remove those players!