Chat messages don't show to some or all other users

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My chat has recently been experiencing some issues. Since the new update, which included crossbows and such, my chat has been unable to work right. This problem is on all of my platforms and it is in and out of servers; so both in my worlds and in servers. I cannot see anyone's chat and everyone is unable to see mine. However, in Mineplex, which is the server I play on most, I am able to communicate using teamchat. Please fix this bug, it would mean a lot to me.