i cant play cf

Hello crossfire community .I am very dissapointed with z8 because i cant play crossfire . When i am playing the game it would either lag or force me to quit from the match because the whole screen freezes. After that i have to close the game as i cant join any matches and i need to wait for awhile before reentering it. This situation happens for about three days a week and no matter how many times i reintsall the cliet it fails to run properly. PLease help me.