Report bug my client freezes and i get afk behaviour

Idk what is happening but each time we are done with champ select the game loads up but it freezes after and it shuts off itself and I can't*[slayer-jinx-unamused]* reconnect cause my team already remakes and so i get leaverbuster 5 games but I didn't leave at all. Funny enough way back it never happens plz riot >_>