Time Stamps not matching

After running a test on the cache I get this error. As you can see, it says timestamps don’t match. The plugin doesn’t seem to making much of a difference to the site and still runs very slow. I’m not sure what the Page 1 and Page 2 means exactly, and I don’t really understand the tips for correcting that. Also, it says the timestamps don’t match but the numbers do? It’s confusing. I’ve heard great things about this plugin and wish I could get it to work properly.

Here’s the error:
Fetching https://dermotmaccormack.net/ to prime cache: OK (0.html)

Fetching first copy of https://dermotmaccormack.net/: OK (1.html)

Fetching second copy of https://dermotmaccormack.net/: OK (2.html)

Page 1: 200 (OK)
Page 2: 200 (OK)
The pages do not match! Timestamps differ or were not found!

Things you can do:

Load your homepage in a logged out browser, check the timestamp at the end of the html source. Load the page again and compare the timestamp. Caching is working if the timestamps match.
Enable logging on the Debug page here. That should help you track down the problem.
You should check Page 1 and Page 2 above for errors. Your local server configuration may not allow your website to access itself.