adobe flash player is not working well I mean since I've trying to watch movie on youtube is not pl

I just wanted to know what to do about adobe flash player is not working the way it should cause I've been trying watch movie on youtube but it won't play I've receiving message said that I need to download flash player which I've done so many times and I still receivr the same message download flash player which I have done I don't know anymore what to do anymore cause I've all the differents things it migh be the problem but still not working, please I need help if you gys know anything that Ihaven't tried yet  help thak you.