Really need help here!

I can’t figure out what’s going on with the latest new engine prime. I never ever had this issue when I had the sc5000. Not sure if am doing something wrong. Every time I load in new tracks going into my playlist and transferring into the usb. My tracks either missing or my tracks are not matching the song titles and other crazy stuff going on. Am not sure if am doing something wrong if so I need a help. I can’t enjoy my new prime 4. I could only load track into the usb stick one time only. Can’t add more new track or else it would not transfer right. Need help denon reps or anyone. Am using a San disk 3.0 usb formatted to fat and my Mac book pro meet all the spec for engine prime