Why can't I speak in game chat?

And i cant remember where to do this or not, or even if its still a thing anymore, but there was an option to test microphones on the xbox as well...also might want to check if the microphone itself is working properly (specifically the microphone)

The easiest way to tell if it is a communications ban from microsoft is to try and start a party if you get an error message that says basically because of your past behavior try doing something else or sometimes it will actually pop up a message saying
that your communications has been suspended till a certain date. Either one of these will tell you for sure that it is a suspension on Microsofts side of things.

Or you could just sign into enforcement.xbox.com with your account and it would tell you if you have an active suspension and how long it is for.

Check that the permissions for that are turned on for your
Microsoft Account Privacy and Online Safety Settings.

Might also want to check if you were comms banned from the game itself? Publishers and developers will sometimes have their own enforcement system which can block or ban actions from your account in their games.

does the mic light up when you speak in chap

Hello! I had problems like that in RB6, try to clear the console cache and synchronize the control again, does this happen in just one game or with everyone?