Server Timeout, although connected to Steam Servers

So, I was in a competitive match. My mate and me were winning 4:1 with 2 minutes remaining. Suddenly I get a server timeout although my internet connection is running fine. I am also still connected to the Steam servers.

I also couldn't reconnect to the server so that I got a 15 minute ban for leaving the match.

This is now the second time that this has happened to me. Is there any way to avoid this? Any help is appreciated.