Hello
Could in some cases be related to the date of the reviews or comments, for example in this url:
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If you see the reviews, you will see that there is a date (see attached image), Google seems to be taking that date to show the results.
You could evaluate hiding the date of the revisions, you would have to do this by modifying the theme files, check: although in the article it is commented to remove all the date, you could evaluate leaving only the date as text instead, something like:
Greetings.
Answered : 05/03/2018 8:52 pm