Friction-free use of apps and services that matter to you is important to us. So, we want to make you aware of a requirement for Skype for Business (SfB) Online to work with MAM policies.
In order to use MAM policies with SfB Online, your SfB Online tenant must be enabled to support modern auth.
If the tenant is not enabled for modern authentication, MAM policies will not get applied to the SfB app on iOS and Android devices. As a result, an end user may see an error message like "Action Blocked: This action is blocked by your IT group." when he/she tries to open a calendar invite from managed Outlook app in order to join a Skype meeting.
How to enable Skype for Business Online tenant for modern authentication
Please follow these steps to enable SfB Online tenant for modern authentication: