Only 10 markers displayed on listings map

Hi,

I've created a map of listings as described in your post. I have added 13 listings but only markers for the 10 most recent posts are displayed. If I unpublish a post who's marker is displayed, then still 10 get displayed (one of the listings that wasn't displayed before now gets displayed).
I've searched the forum and also other places to find information on this problem, but wasn't successful.
Can you tell me what the issue could be?

Here is the page:
https://marchemondiale.org/index.php/5th-international-action-8-march-17-october-2020/24-hours-of-feminist-solidarity-against-the-power-of-transnational-corporations/

Here is the JS code:
https://pastebin.com/0LPVcym0

And here is the code added to functions.php:
https://pastebin.com/ch4dtuCu