Retrieving lost notes from iPhone's local storage

Two weeks ago, I turned on Sync this iPhone for notes and ended up losing hundreds of notes on my phone because the "On my iPhone Account" wasn't switched on. Which I found out is default off for all new apple products. These notes were not saved to the cloud or an email account attached to notes so they are not backed up anywhere and wasn't able to get them back after visiting the Genius Bar. I'm hoping there's a possibility of using some sort of software to retrieve them from my phone as they are incredibly important.

[Re-Titled by Moderator]

Original Title: Retrieve notes from hardware