with evry warlock clas it does nothing when the mob comes close

I tryed mikes warlock class to but it does nothing just waits til mob is dead if he comes close he doesend cast anymore how do i fix this?

 

lvl 2 yes i have a imp but if a mob comes close he just stop casting spels and the imp does the rest wil that be other while he gets higher my hunters is going great but a warlock stop when a mob comnes close

 

Please post a log of when it happens, so we can see what it's being caused by