Automated Definitions update not working

Automated Definitions update not working

Hi,
I'm testing PMP 10.0.604.
I've set up automated deployment for Windows Defender definitions and added 2 computers to receive this automated update.
PMP shows that both are "sucessfully updated". However, checking manually, one is updated with latest definitions, and other one isn't.
So, then I created manual deployment for patch id 400009 AV-FCS03 (The latest update for Windows Defender (1.339.103.0)) and added this computer that isn't updated via automated patch deployment task.
After executing manual deployment task, task completed stating "Not Applicable".
And again, definitions on target machine are out of date and not updated.
Third step i to manually get *mpam-fe*.exe file from /webapps/.../store folder, copy it to this machine, executed it and definitions are updated.

So, where's the catch?
Both machines have same configurations, same os (W 2016 Std), both are domain members, both agents successfully scanned machines, installed Windows Cumulative updates, etc etc etc...
Ideas? Suggestions?
Thank you.