Look to the left of the audio track/s to confirm whether they have been either muted.
In the same area, to the left of the audio track that you can hear, did SOLO accidentally get clicked? That would mute the other tracks.
If no joy, please click FILE|SAVE AS PORTABLE PROJECT and upload the file that results to a server, such as MS OneDrive, Google Drive, etc. and link it here. Someone will check it out.