My 64Gb IPad Air 2 shows that the storage is full, but adding up all the apps and documents it only comes to 3Gb. I do not have photos, videos or music on it as I use it for work. I can find no way to identify the other 50Gb plus of data that is stored some where. I have also deleted all unused apps and done hard resets. Any ideas would be greatly appreciated before it gets a very hard reset.