Host sleeps, guest frozen/black screen

[mangoms]

Ubuntu 18.04 host
Windows 10 pro guest

Had this issue for a while, cant figure out whats wrong.

After around 2 hours Linux will sleep, then VBox shuts down, cant RDP to VM and the server hosted on my VM is unreachable.
When I connect to my host machine I can see VBox open, but VM has black screen. When I move it around I can see Windows 10's lock screen. If I try to click on it to log in, it will start the animation between lock screen to password box, but its stuck inbetween - so I can't enter my password, until it goes back to the lock screen.

I've tried changing power setting on host to never put display to sleep, but still happens.

Attached is a .zip with the log.