I have a Microsoft Lumia 640 LTE running windows 10. I now get a warning that 7.28 of 7.28 GB of my device memory is used. It seems that the mail and calendar app is using an awful lot of the memory, over 2.5 GB, no matter that I erased just about every email I have. I dont take alot of pictures, movies, actually the phone is only about a month old. I do have a 16 GB SD card installed as well and cannot move any more apps or files over to it that I can find. Anyone know what I can do to stop this from happening?