Recovery from backup reverts to newer document

[Diplomat2thegalaxy]

I apparently did a cut-and-paste that erased the majority of my book. When I go to recovery, it shows the rough draft at 85,000 words. Then, when I do either copy/paste or duplicate, it momentarily shows the 85K at the bottom of the document, but then reverts it to the newer version in which there is only 18K words. I tried different dates for recovery, but this persits in all of them. Any suggestions? Thanks. 

[#2]

What shows up if you press Alt+F9 to reveal field codes?
While working on this, make backups of any recovery files.

[#3]

Spoiler

There are 2 things I should have clarified. One is that I am using a Mac so I don't have an Alt or an F9, and the other is that I am older so not as tech-savvy as younger people are. Can you tell me what you said in Mac language? Thank you. 

[#4]

Opt+F9 which toggles display of field codes. It is possible that much of your document was swallowed by a field.

Thank you. I receive Social Security retirement!

[#5 · Accepted solution]

Lol. That's how I feel, like I've been swallowed by a field, swimming in a sea of technical mysteries. Is this a symptom of alien abduction? (It's a common symptom that electronics act weirdly afterward.) I got some help from a friend who had me do an update and then the document appeared whole again. He also suggested that my old computer may need to be replaced.