Intermittent Enumeration of Resources: Some apps and desktops enumerations are missing at the user's Store, and appear back intermittently after reauthenticating to the Store.

1. The Security Groups have to be configured with Universal Scope in the Active Directory instead of Global. 
2. In some cases, the issue happens due to an outdated Cloud Connector, which can be resolved by
   • Removing the Cloud Connectors from the Resource Location, one by one.
   • Uninstalling the installed version, and reinstalling the latest version available.
   • Restarting the Cloud Connectors, one by one.

Problem Cause

Problem with the Scope of the Security Groups of the users whose enumeration fail intermittently.

When using Active Directory groups to assign resources, the groups should be configured with a Security Type of "Universal" instead of "Global". 

https://docs.citrix.com/en-us/citrix-workspace/secure.html#azure-active-directory