HP 15 Screen does NOT turn on!

So, I got this HP 15 for my fiance about a MONTH ago and he's already having issues. The switch on the bottom that is SUPPOSED to hold the battery in, is loose and the battery partially came out and turned off the computer. I put the battery back in and then tried to power it up and I got a black screen. When I turn the laptop on, it sounds like it is booting up, and then gets VERY quiet about two minutes later. All the lights on the keyboard stay lit too. I would LOVE to know what is going on with it because even the people at HP have no clue. Someone please HELPPP!