Oops! Google Chrome could not connect to face

Hello,

an engineer came to our home and operated my computer. after his vacation, i tried to open facebook site but a message stating Oops! Google Chrome could not connect to facebook.com flashed on my screen. it has been a month since i have tried to operate facebook but all in vain. and most interesting thing is that only facebook site is unoperated while other sites function as they do always.
please get me a way to get rid of this