Images Dropping Out

Hi,
I’m a new user to GD, using WP Multisite 4.5 and GD 1.5.9

I’m having a problem with Places. I’ve dropped image files onto the individual Place listings, I see them all load, and I see small thumbnails of each, and I clicked “Update” for each.

Each of the images dropped are jpg files and range in size from 75kb to 750kb.

Then, when I go view the site, almost none of the images appear. In fact, all but one dropped out.

And, when I go back into the admin for any of the Place listings, the Places Attachments area is blank, so all of the files and thumbnails are no longer there.

I’ve checked the month/year uploading, and that has been checked “1” for yes.

Please help,
Robert