Hi midikid,
It seems that the WNC service (that is used by Focus Assist) have problem when it's turned off and on (we reported this to Microsoft). But something must trigger DnD mode to stop the service. Do you have some wierd apps in your DnD mode app list? If so can you send me the list from your hard drive (located in: C:\Program Data\AVAST Software\Avast\gaming_mode\games.json, you might also want to disable avast self defence for a minute (Settings>Troubleshooting>Enable Avast self defence module) and stop avast service for a minute to copy that file
).
If you don't have any weird apps in that list, you can just try to disable option to silence notifications from 3rd-party apps, that might help.
If that doesn't help, can you please turn on debug logging in Settings>General>Maintenance>Enable debug logging, reproduce your issue and then send me DnD log from C:\Program Data\AVAST Software\Avast\log\GamingMode.log (you need to do same things as for the game list).
Also some more info about this problem:
https://forum.avast.com/index.php?topic=222394.0UPDATE:
I tried waking up computer with the WNC service stuck at Stopping and Windows didn't create new instance of the service. So your problem might be occurring before you put your computer to sleep.