text doc now spreadsheet

I had a text document and for some reason it became a spreedsheet. How do I change it back. I never even opened it, just seen it was different, and now it is not what I saved.

We will need more information to be able to help. How did you see “it was different”? Perhaps the extension of the file is wrong? How does it look when you open the file? Could you provide some screenshots? Additionally, it is always good if you declare your Operating System and LibreOffive version.