Skype for Business - Video calls drops after 10 seconds and file transfer doens't work.

Hello guys,

I'm using Sophos XG230, and I'm having problems with Skype for Business. Video calls drop after 10 seconds.
And file transfer also does not work. I have tried some approaches such as the release with application rules or through firewall rules without HTTPS inspection and releasing all domains used by Skype.
None solved the problem. Can someone help me? What is the correct way to release Skype for Business?

Thanks!