I can't play the game [client]

today a wanted to play league but when in championselect, the timer stoped at 0 everyone was still there, I could chat with them and everything. Finally when the game started everything run smothly as normal. Then when the enemyteam killed the nexus, the defeat screen didnt pop up so i couldn't click away. the game was over so I thought I could just leave. Even then the client sais I'm in game and that I should connect, BUT THE GAME IS OVER. after several times of trying to "reconect" but it kept crashing I gave up. Now about 2 hours later I still get the same message that I still have a game in progress. That means I can't play the game since I don't have a smurf. These client issues is starting to get a little bit annoying now, after patch 6.8 more and more issues have occured. It's not my computer since I bought it in the beginning of this season and everything has been fine, until recently. Please if someone could help me or maybe give some clearification over my problem and what to do I would really appreciate it.