"Enable to connect to the game" message received for no reason while joing a game

Hey,

In ranked it happens to me sometimes, after champ selection i got a message saying im no connected (but i am...) so i restart the client but still the same, i disconnected from my box and connected again and still the same.

I was in promo so it's quite frustrating, any ideas ?

Thanks in advance, LeeSinToMyCalls