I can't connect to a competitive match with people on my friends list, but I can play by myself. It's happening on both my accounts, I can enter a lobby click go and it works but then when it says "confirming match" it says "[My username] failed to accept", or my friend failed to accept, when there was no Accept button. Any ideas?
Sometimes CSGO seems to think you are not logged into steam. The only way i fixed this happening to me when it happens was to have every party in the lobby completely close steam, reconnect and then re-open the game and then it was usually ok.
Another time this has happened was a problem with steams servers experiencing above expected traffic. Eventually as servers calmed down it functioned agian.