Problem with uploading tracks

Hi. New here. I tried to upload my first track. I prepared the main track in wave and mp3 format, plus the preview track in mp3. I zipped the two main files together (wave and 320 kbp mp3). I uploaded both the preview mp3 and the zip file and selected them at the approriate field. I am still getting the message: “audio file must be set”? What am I doing wrong here?!

You just have to select MP3 and WAV so they are highlighted (as per below)


Oh, I did not know that. I will try again, and see. Cheers!