Just like in iOS versions of Outlook and OneDrive please enable multiple identities on Teams when Managed by InTune. I can’t login to any of my other tenants from my iPhone when managed by InTune. You are forced to un-enroll your device to be able to login to a second or more team accounts.

I can handle only login into one account at a time however please allow at least that to happen when the device is registered in InTune