Outlook still works after Company Portal is removed

[BENT17]

I have configured intune policies & conditional access for my Android and iOS devices, however when I come to my Windows 10 devices, when I remove the company portal my outlook application sill has my emails. I want outlook to stop working when Company portal gets removed. 

Can someone point me in the right direction please? 

[#2]

@BENT17  - We went through something similar to this as well, and per MS the recommenced solution was to make Outlook a required application on any enrolled device. Otherwise it doesn't properly remove when a end-user breaks enrollment.