LR Mobile not downloading photos

 I can't get the photo editor on my tablet to download my photos. Sometimes I can't even get the phototo load so I can edit it. I have removed half the photos I have had stored on my tablet, added a new SD card, Uninstalled and reinstalled the app. I have closed the program and reopened it several different times, I have restarted and also done complete power downs on my tablet.  I am still having the same issue. Once in a while I can get a photo to load, I can edit it, and sometimes it will even save in a timely manner, then the next photo I go to edit all I get is that spinning circle for several minutes before it times out and says it can't  load. Or I will edit the photo and when I go to download it to my tablet all I get is the spinning wheel. I have spent over 12 hours over the past week trying to make this work, reading on what I should do. This has been happening over the past week or two. What is wrong! Help! I use a Samsung tablet that is less than a year old!