Camera option greyed out

I am having the same issue, but not with my usual weekly zoom. I received a zoom invitation from a university and the normal options on the bottom don’t show at all. I get a pop/up where I should be, but only see a generic person outline, the audio control that I can turn off and on, and the greyed out camera icon that has a slash that I can’t toggle on. 

I uninstalled and reinstalled Zoom. No change. Again, my weekly zoom works fine.