Can't join my friends' games since yesterday 12/1

Since yesterday I haven't been able to join my friends' games. When I try to it just comes up with the box when you try and join someones game and it's full. The odd part is that the only two options are close and refresh and sometimes join game but that never works. I checked and nothing is wrong with my firewall. Also, I can join games through browse servers. If somebody could help that would be great.