Although there’s no way to directly reset your password, fortunately, Noted utilises iCloud Keychain to securely manage your notes password.

If you’re on a Mac, you can view or change this via Keychain Access. 

1. Search for com.digitalworkroom.noted
2. Locate the item named password and double click
3. Click Show Password to reveal or change

Ensure iCloud Keychain is enabled on all your devices so changes are synced across.