I am unable to open old files on GarageBand

After the recent updates, I am not able to open the old files. I get the message that The file couldn’t be opened because it isn’t in the correct format. Though I have these saved as mp3 files also, I would like to recover the notes that I added to them as I was editing the .band files. Kindly suggest how to go about to retrieve these files and notes. Thanks



[Re-Titled by Moderator]