Did you receive an error message when trying to upload your music? If so, then you've come to the right place.
Our best recommendation is to re-export the file(s) from your audio editing software as 320 kbps MP3 files. Once your files are at the correct bitrate, you'll be all set to upload. You can find helpful articles about exporting here.
If you had an engineer create the files for you, message them letting them know you need your tracks as 320 kbps MP3 files.