Earlier this month Microsoft announced it was making a few changes to its OneDrive services, and this was to do with free storage it offers. When users first signed up for their OneDrive you got 15GB of free storage, and if you connected up your camera app to backup your photos you got another 15GB.
Microsoft are looking to discontinue the Camera Roll Bonus and instead of 15GB you will end up with 5GB. These changes will be happening early 2016.
You can keep your free storage but you have to opt in to do this. Click on the url link https://preview.onedrive.com/bonus/ and sign into your OneDrive account.