Solved doing the following:
- Uninstall MS Teams
- Install MS Teams Classic 1.8.00.4966
- Login (and switch to your organization if needed)
- Teams will automatically update after a couple of minutes, when the window appears tell it to "Try the new Teams on the web"
- Wait fot the web page to open
- Close the web page and return to MS Teams Classic
- The update window show be gone if not click on "Continue using classic Teams"
- Now slide the "Try the new Teams" switch in the upper left corner of the app window
- Another MS Teams app will start (it will have a "NEW" blue label on the icon)
- Close the app
- Start the "Microsoft Teams New" app again
- Now the "Microsoft Teams New" should disappear and be replaced by "Microsoft Teams"
- Leave both "Microsoft Teams" and "Microsoft Teams Classic" installed