Hi,
Check this and could be the reason the way it was setup users cannot see the App - https://learn.microsoft.com/en-us/troubleshoot/mem/intune/app-management/apps-appear-unavailable
or the other way is offline - https://learn.microsoft.com/en-us/mem/intune/apps/store-apps-company-portal-app?source=recommendations
Hope this helps.
JS
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