Can’t save audio

Hi i can’t seem to save my audio. I saved it before and shared it with a friend and it worked but now it doesn’t? I usually save it as a lossless file and it was fine before but now 2 tracks from the audio is saved as nothing? Like the other 2 tracks are saved as WAV but the other two is just empty file :neutral_face:

To create a WAV file, use “File menu > Export > Export at WAV” rather than the “Save” command.