MS Teams Navigator Window not available

Hello 

I am working in Mac OS X 10.15.5 on a MacBook Pro (Retina, 13-inch, Late 2013).

When I am using the Team app, I have the bar at the bottom but the Navigator Bar which is supposed to be on the left, doesn't show up. I've quit the app and logged back in and have joined different meetings. I haven't yet restarted the computer after install. Any suggestions ? Thanks