It could be the battery is just dead and needs replacing or the charging circuit. If the laptop is under warranty, then you should contact the manufacturer. If it isn't under warranty, then I suggest you seek a replacement battery. Just make sure to replace it with an OEM one and not an aftermarket, as those can lead to a host of other problems.
Now if you don't want to try and replace it without further info, and if not under warranty, then you can always try taking it to a local tech and have them test it.