1. Navigate to the player's Profile
  2. Tap on the 3 dots in the top right hand side of the screen
  3. Tap on 'Block User" 
  4. Enter a reason for blocking the user 
  5. Tap OK The user will not be able to create NEW games, chat or contact you at all. 
*Note: If you have existing games with the player in question, they will be immediately resigned. Both the blocked and blocker will no longer be able to interact, create games or chat with the other player.
To remove a blocked player, go to the Privacy section in Options available under Settings and select "Manage Block List". You will then be able to select user and unblock them. Only the user that has blocked the other user is able to unblock them.