As a host of multiplayer world (no realm), I was able to send messages to others shown in chat and in theirs, too. But, I can't see or at least not showing messages from others in my chat. The settings is default. No communication blocking. I am an adult that use master xbox account.
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I found the problem.
Messages will not be displayed in my chat when they have been put on mute. I must have accidently put them on mute somehow from friends' profiles.
Thank you for your report!
We're already tracking this issue at MCPE-45385, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated. If you haven't already, you might like to make use of the search feature to see if the issue has already been mentioned.
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