Wireless interface missing

Hi there, I bought my fiance a dell laptop. It used to work on our wifi but now it doesn't. When I look at the Network Settings there is only "Wired connection" and "Point to point connection". I have looked through lots of help subjects and it seems the wireless interface is missing? I really don't know how this has happened, I've tried for hours to try and get it to work but to be honest it's just like