They posted in forums as well. I have no idea what versions they are using nor anything about their WP admin. In the future please follow the posting guidelines and provide a screenshot of the SLP plug-in environment. The screenshot you are showing does not provide any information to assist you.
If you open their url using any browser tools and look at their site inspect console have 134 warnings about Mixed content. This suggests that their site was not migrated correctly.
This can cause issues in back end and front end, or it is possible not all their data and locations were migrated to the new site.