Do you have Zorin OS installed as dual-boot alongside Windows? If so, try disabling secure boot, fast boot, etc. Those settings can interfere with power management.
However, unfortunately, the latest release of Zorin OS has proven to be buggy in this regard as reported by others. What I would suggest for the time being is to prevent your system from going into suspend, and also from turning off the screen. You can do this from Settings → Power.
This isn't ideal, but I find it's more important to have something that works more consistently while this remains a known bug.