What's wrong with it?

My Philips Livingcolors 2 lamp isn't really working. The cleaners left it on for god knows how long upside down because they didn't know how to turn it off and decided not to tell/ask anyone (meanies). So, it's only showing certain colors and I'm wondering if that means it's just tired or I need to replace the bulbs, if I do need to replace them, then what type of bulb would I use?