Overnight My Monitor Disconnects & Won't Turn Back On?

Hi! I leave an idle game and uTorrent on overnight but turn the monitor off.
Occasionally I go to turn it on in the morning & it says "No Signal".
Only turning the PC off restores it. Also the PC won't shut off with the power button, is that normal?
Windows 10, Benq monitor. This started maybe 2 months ago? It's happened 3-4 times now.
Thanks!

Check for a video driver update, if no update available remove and reinstall what you have.

please check in the device manager for your display and graphics card
right click each entry then properties

if there is a power management tab make sure
'allow this computer to turn off this device to save power'
is disabled

i do this to any and all device manager entries to ensure my system stays on.
best of luck Steve ..