If the school exists and you really took the classes, they are not gone.
I assume your HS has a copy and/or your counselor can help if not.
You may have to pay for the transcript or if you audited, then didn’t get a grade.
But what you are saying, assuming it’s an accredited school, that story is not going to be bought…and on top of that, you are saying you took the classes…are you just going to let 6 classes you took at the college level that show your competence of college level work slip away?? That helps your chances.