You may want to look here:
viewtopic.php?f=5&t=15282Particularly this section of that post (reproduced here)...
ezymel wrote:When I am using Zorin, and I leave my computer with the lid open,everything is fine. When I close the lid, and reopen it. everything is frozen up. No activity whatsoever. I have to manually close it down and once booted up again, it works fine. Windows, I have no trouble with when I close the lid. The only thing that I can surmise is that Zorin goes into sleep mode and it is a deep sleep. Ha ha. It must be some kind of some glitch but I am not going to worry about it.
Aravisian wrote:This is a known bug with Ubuntu and I do not know of a good, solid solution. It affects some computers and of those, a small percentage respond to certain workarounds or "fixes" while some do not.
On my current machine, I am not affected. But my last one was. I got used to holding the power button down...
You could try the Lid Switch Fix:
http://tipsonubuntu.com/2018/04/28/chan ... 18-04-lts/https://askubuntu.com/questions/1046826 ... laptop-lidAlso, using your Power Settings Manager, you can try setting all options to "never."
Another post about it here:
viewtopic.php?f=5&t=15231