If you get a large black rectangle in the bottom center of the screen when you change the settings on Apple TV to 4K HDR. What should we do?

Following steps to see if it solves the issue

Please try performing a factory reset by going to Settings> General> Factory Reset.
Once the projector is reset, please make sure that the projector has the latest firmware.
This can be done by going to Settings>General>Update version. Please update the projector if it is not up to date.

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