Unsupported file message

I am frustrated! No matter what I do, I can’t transfer songs from Apple music on my mac to the clip jam! Drag and drop does not work. Copying and pasting each song to the music folder on the clip jam worked, but the music on my player showed no songs…the songs could be accessed in folder mode…but an “unsupported file” message resulted for every song! Then I tried changing the format in Apple music to AAC and/or MP3…nothing! This device might go back soon! Can anyone advise?
Thank you!!!