You can't roll back to earlier saved versions of a note unless you have the Premium version, which I don't.
But I got it resolved.
I contacted @evernotehelps on Twitter but received no response. And also wrote to several moderators of Evernote I found scrolling through the forums, and also received no response from most of them. However, eventually I received a response from one, who converted my message to a ticket. After this, an agent from Evernote contacted me via the email I had provided in the message I originally sent. They gave my account a temporary upgrade to use the services of the Evernote Premium - specifically so I can use the Note History feature - so I can restore the previous version of the note, which I did. I hope this helps.
