wifi cannot connect microsoft teams app to internet

dell xps 13 ( 9360).

As of 1 week ago the microsoft teams desktop app stopped working. Cannot login. 

Message received is "cannot connect to endpoint"

After a long troubleshoot session ( installed all windows updates, re-installed the app, cleaned several teams folders like cache in the \%appdata%\teams folder, etc) 

I discovered that when i use the ethernet cable to connect to the modem, i can connect fine.