Use this guide to force update SCCM device collection groups and update the full list of devices if a group isn't updating by itself.

1. Start a remote desktop session on MRS-RDP and log in with your administrator credentials.
   
   
   
2. In the start menu, find Microsoft Configuration Manager > Configuration Manager Console.
   
   
   
3. Click on Device Collections on the right hand side.
   
   
   
4. Right click on the group you want to update membership for, then click Update Membership.
   
   
   
5. Wait a few minutes for the group to update, then click the refresh button in the top right of the UI. You should see the member count update.
   
   
   
6. If you need to see what members are being added, right click on the group and then click Properties.
   
   
7. Click Membership Rules to check how computers are being added to this group. In this case it is an AD query. See https://helpdesk.mopt.vic.gov.au/a/solutions/articles/75000143832 for more details.
   
   
   
8. If computers are still not being added to the group properly, you should run a system discovery. Keep following this guide to update the AD system discovery.
   
   
9. Click on Administration, then Discovery Methods.
   
   
   
10. Click on Active Directory System Discovery and click Run Full Discovery Now.
    
    
    
11. Wait 15 minutes, then check your device collection again - you may need to repeat steps 4-5 again to update memberships once the computer has been recognised.