Hi Jitendra, you need to procure license from Cisco in order to activate MSTeams functionality via CVI Integration.
Guide as already mentioned here:https://help.webex.com/en-us/article/nffx8kj/Deploy-the-Webex-video-integration-for-Microsoft-Teams
Hi Steig,ja
Kindly upgrade the device to latest released version RoomOS 10.15.3.0, this issue should be fixed.
You may also alternatively upgrade to RoomOS 10.11.5.2 and test again.