Mac Computer stoped working with League of Legends program

Ive been playing LoL for years on my Mac book, but today when i got on to log in the gme will not allow me to play. The game will allow me to log in, select a game type, select my character of choice. but when the game switches screens to load my screen flips to the information screen stating that the "game is in progress". i have uninstalled the game completely twice and tried restarting the computer after each install but it give the same failing result. has anyone else had this problem? anyone have any idea why this happened?