The chat may become unavailable when there is an instability in our server, or due to connectivity issues. Please try the following steps and check if the issue gets any better:
  1. Reopen the game;
  2. Restart your connection;
  3. Restart your device.
Please do keep in mind that the game may have a slower performance right after updates. So if you have recently updated your game, try to play for a couple of days and check if the problem persists.