Networked WP "Deactivate" a blog site then later "Activate" it loses posts and comments

[johngoold]

Site dashboard shows WP version as 4.9.10 (does that equal 5.0?).

Using network administration, the list of sites shows the following when hovering over a given site:

Edit | Dashboard | Deactivate | Archive |Spam | Delete | Visit

Selecting "Deactivate" appears to work. The blog site is not deleted (confirmed) and none of the posts appear to be retrieved. Attempting to access the blog site provides an appropriate message (versus a 404 not found or similar).

However, a day or two later, when the site is "Activated", all the recent posts and comments appear to have been deleted (i.e. no longer visible). This involved the years 2016 - 2019. Previous posts and comments going back several years were retained and can be displayed.

The only vaguely similar issue I could find is #44515; but clearly I used "Deactivate" or I would not have been able to re"Activate" the blog site.

Note 1: The networked setup uses sub-domains.

Note 2: Using phpMyAdmin to view the records in wp_13_posts (the particular blog site involved has the Id 13), there are rows for the years 2018 and 2019 -- 8 for 2018 and 7 for 2019. The "post_content" column for these records appears blank. The "post_title" column appears to indicate these are entries associated with a post, but not the "main" post. Those with a post_title like "Rev-9-MAR-2019-Sectional.jpg" have a post_type of "attachment" and post_title "Auto Draft" have a post_type of "post".