I have the exact same problem. I've put it down to not wanting to wake up, because I can be awake perfectly fine by my clock, but I always choose to go back to sleep / choose to ignore my alarm, which has become an automatic habit at this point. The only exception is if I have something to attend to, but even then I leave it as late as possible. I do this automatically now because I've done it so many times, but it only started during a dark part of my life so I've put the problem down to depression and hating being awake, because it means returning to my problems.

Sleep is an escape. It's one of the easiest forms. I've been working on healing myself the past few months by doing therapy, and finding new ways to enjoy life (even something as simple as picking up a new video game). This is quite a hard question to answer and please don't take insult.. have you thought that maybe you hate your life? Why would you wake up to a life you hate? I don't ask this out of spite, I ask this out of commonality. Possibly the solution to your problem lies in facing what you're escaping from.

Maybe you have problems with your job? Maybe you have problems with your family? How is your dating/sex life? etc. These are all personal questions, please don't answer, but instead try to ask them to yourself. Then realise that if you are, like me, using sleep as an escape then you will need to, right now or as soon as possible, work on fixing the areas of your life that you're running from / suppressing. For me it was childhood trauma and abuse, it wasn't until I started therapy and started the process of deep self-healing that my problem started to lift, where life started to become bright again.