Hi there and welcome
With it open press CTRL and Z
Does this bring the text back?
Ok, then it will be lost sorry. Notepad is a very basic program and has no auto backups.
I advise you always press CTRL + S as your using it to ensure you are actually saving the file to the computer
If you would like any additional information or assistance, please do not hesitate to let me know.
Else if you can take a second to rate my service by clicking one of the stars at the top of the screen then submit, that would be greatly appreciated.