If you "saved" the Audacity project (File menu > Save), then the project will still have the original track layout.
That is probably your only chance of recovering the separate tracks.
See here about the difference between saving and exporting: http://manual.audacityteam.org/o/man/au ... jects.html
file was mixed into 2 stereo channels on saving - undoable?
Forum rules
This forum is for Audacity on Windows.
Please state which version of Windows you are using,
and the exact three-section version number of Audacity from "Help menu > About Audacity".
Audacity 1.2.x and 1.3.x are obsolete and no longer supported. If you still have those versions, please upgrade at https://www.audacityteam.org/download/.
The old forums for those versions are now closed, but you can still read the archives of the 1.2.x and 1.3.x forums.
This forum is for Audacity on Windows.Please state which version of Windows you are using,
and the exact three-section version number of Audacity from "Help menu > About Audacity".
Audacity 1.2.x and 1.3.x are obsolete and no longer supported. If you still have those versions, please upgrade at https://www.audacityteam.org/download/.
The old forums for those versions are now closed, but you can still read the archives of the 1.2.x and 1.3.x forums.
Re: file was mixed into 2 stereo channels on saving - undoab
9/10 questions are answered in the FREQUENTLY ASKED QUESTIONS (FAQ)