Can't connect to game

After Champ select I don't connect to the loading screen. Instead there is the normal League of Legends window and a button which says "Reconnect". Whenever I press it there is a short loading time and it says "Game is still in progress..." and then the button to "Reconnect" pops up again. And again. And Again. I tried to close and open League, rebooted my PC and even turned off my internet and on again. Nothing works.

I would be happy if someone can help me :)