All of my Notes in the Notes App have disappeared!

All of my notes in the notepad have disappeared! Countless hours, months , years of work are gone ! I contacted Apple support and they were no help. If I can’t rely on the phone it’s of no use to me.

This happened a number of years ago after an update. Apple was very apologetic and said they would fix it. Obviously they have not.

[Re-Titled by Moderator]