@Alpesh005, Thanks for posting in Q&A.
According to your description, company portal was installed for your company mail access on your personal phone, there may be some app protection policies or condition access policies in Intune to protect you company apps.
If you do not want to install unnecessary apps and do not want them to pop up, you can assign these apps as available, so that you will not receive the prompts.
https://learn.microsoft.com/en-us/mem/intune/apps/apps-deploy#assign-an-app
Or if you do not want Intune to manage your own personal apps, you can check if there exist app protection policies for your own personal apps, you can unassigned or remove them, after that Intune will not manage you own apps.
Hope above information can be helpful, if there is any update, feel free to let me know.
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