My champions keep freezing and wont move or use spells

This has been happening over the course of several days getting worse every game I play. Basically the game continues as normal, everyone else moves and uses abilities in real time. But my champion wont move or use abilities he just stands there for like 5-10 seconds and gets killed. this has killed me at least 3-4 times a game for my past 20 games or so. I know I don't have lag issues i play several other multiplayer games and have never had a problem with them. It isn't even lag my ping stays the same at around a constant 20-40 but its like the ground grows hands and holds me down for the enemy to kill I cant even flash or use abilities while they just wreck me.

I have a 2 month old Alienware computer which runs games like overwatch and the witcher 3 at highest settings with no problem and have had no problems running league in the past on it. This only came up with the recent patch, its game breaking I cant play the game like this. and ive paid for almost 100 dollars worth of skins. Please respond soon I don't want to have to get a new favorite game.