Notes
How can I recover an old password in my Notes account
Question marked as
From the article below.
To unlock a note, you need to enter the password that it's locked with. If you forgot the password, Apple can't help you regain access to your locked notes. You can create a new password, but this won’t give you access to your old notes.
How to lock or unlock notes on your iPhone, iPad, and iPod touch - Apple Support