perhaps you have bad sectors on your cf card… the question is how it comes to this bug. cf cards are actually robust and there must be a file system “auto-save” failure with the octatrack because it happens too often, if you read in this forum. perhaps the best way to handle this is to have always a backup version of your project. i know it isn’t supposed to be with a 1200€ machine…
and contact elektron support!
cheers and luck!