If they are a guest there seems to be a bug in the latest admin center rollouts causing the meet now and group call functions to not work for guests which would most likely include these type of calls too. When you give over the meet now it says something about not being licensed for the feature. I would call Microsoft and get a ticket in as well. I. Mobile so hard to find other thread but if you search for guest meet now and in past week in filter should show up. But definitely a bug getting pushed out.
Any update on this issues? I cannot join group meetings on Teams using the desktop app but can use all other functions. It will allow me to join via the web app but that does not allow me to share and present items I need to in meeting as a web user.@Laura Bray
I have the same problem. Everything works in Web version, just not the App. App version says version 1.0, however in Control Panel > Programs and Features I see 1.2.00.13765 installed, and the install date is the same date when the problems started. Will post a fix should I find one.