How can I recover a deleted note on iPhone?
How can I retrieve a deleted note that I had with important info on my contact person's NOTE info?
[Re-Titled by Moderator]
If the deleted note is not still in the trash, it is gone.
If you're missing notes on your iPhone, iPad, or iPod touch - Apple Support
Some mail servers may have a means to restore messages or deleted notes that were stored on that particular mail server. How that works (and whether the feature is even available) is server-specific. But I would not expect that.