@Asnor Mohamad Iqbal Bin Agus Salam Thanks for posting in our Q&A.
For this issue, it is suggested to add the target user group in "Available for enrolled devices" when you deploy apps. When these users sign in the company portal app, they can install app from the Company Portal app or website.
https://learn.microsoft.com/en-us/mem/intune/apps/apps-deploy#assign-an-app
Hope it will help.
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