Map and result list appear empty

Hi,
I have the Store Locator installed and working very well on several sites.
I have recently installed it on a new site, and on the page I can see the search line at the top of the window, but the map and the results areas are completely empty (the code is empty).
The settings are the same as on other sites, and I have tried disabling all other plugins and changing the theme, but it didn’t help.
What could be the issue?
Thank you for any help.