This is the 3d time this has happened. When saving a 45 minute file in which I put hours of work. This new version erases data producing lenghly flat-lines in the sound file. I have lost HOURS of work. I no longer trust this program. (I have been using Sound Forge for years.)
Sorry I have no viable answers. But in the future, 'Save as; a Sound Forge project, which will create a <.frg> EDL file and folder, Then "Render as" a PCM file from that. If there are glitches (or other issues) you will not 'lose' any work.