auto heal not saving

I'm very new to adobe. I'm using audition to edit audio from a video clip. I have figured out how to use the lasso tool to select a part of the audio I want to fix, then I used auto heal. However the auto heal is not staying on the clip. If I save the audio, it's just the original audio when I play it back. I can't figure out how to make the auto healed selection stay as part of the final product. I've watched videos where people use the auto heal tool and I'm not doing anything different as far as I can tell. My selection will also disappear if I click outside of the shape I lasso-ed, even though I already applied auto heal to it.