This is usually a problem with display connection quality. Please try a different HDMI cable.
Also next time the problem happens please run:
journalctl -b0 > journal.txt grep . /sys/class/drm/*/status > connections.txt sudo apt install drm-info drm_info > drminfo.txt
and attach the resulting text files here.
This is usually a problem with display connection quality. Please try a different HDMI cable.
Also next time the problem happens please run:
journalctl -b0 > journal.txt drm/*/status > connections.txt
grep . /sys/class/
sudo apt install drm-info
drm_info > drminfo.txt
and attach the resulting text files here.