The fix can be as simple as checking that the HDMI cable is properly plugged in. The Raspberry Pi 4 has two HDMI ports, and the one marked "HDMI0" requires a cable for the unit to project properly.
This usually happens because the Pi’s default HDMI settings don’t always ... or enabling disable_overscan=1 can help fix cropped edges. The Raspberry Pi’s USB ports have a limited power ...