Some SCCM Clients not Receiving Updates, Some do

Hello Friends

I am facing a rather weird issue with my SCCM server, happened out of a blue, as no settings have been changed on our server.
To make it easier to understand Lets say I have 2 deployments, and 2 collections.

Deployment A & B

Collection A & B

The issue is, some device in Collection 'A' receive the updates in Deployment 'A' and some of them don't. Those devices however, will receive updates from Deployment 'B'. Same thing happening for Collection 'B'.

Now this is just an example and the devices, updates might not be exactly the same, but the main point is, some devices receive some updates and wont receive others.

For example, I have defender updates being sent to all devices every day as an auto-deployment rule which works for the devices in collections I am talking about, but when I pushed manual monthly patches yesterday, only 3 devices received the updates and the rest are just staying in the state of "Client Check Passed/Active".

I believe for some reason the client is not seeing the updates for a specific deployment package

That all being said, I did try numerous troubleshooting methods, as follow.

• Reinstalling the SCCM client on of the devices
• Deleting the SCCM certificate from the device and for gpupdate
• Clearing SCCM cache and SoftwareDistribution folder
• Deleting the Deployment package and redeploying the updates all together
• Uninstalling the update from the last month on the SCCM server, in case there was a conflict

I have reviewed the following logs on the client:

• UpdatesDeployment
  • In UpdatesDeployment I see that there is no update for installation
• WUA Handler
  • Here I see the following errors:
    • 
• WindowsUpdate
  • Here I see the following errors:
    • Any help would be greatly appreciated.