I have a 64gb iPhone 6 on iOS 8.4 the phone storage itself I've used 15.5gb with 40.3 available storage. And on the iCloud I have 13gb available for use. I originally started receicing the "Not enough atorage to update your iCloud" message before I upgraded my storage capacity. Now that I've upgraded it I'm STILL receiving this error message when I obviously have PLENTY of room. I've tried a soft reset on my phone and that didn't seem to work. Please help me fix this problem!