After opening the plugin editor I see the problem. The plugin is installed incorrectly, it's under the folder “ajax-search-pro2” instead of “ajax-search-pro”. Please deactivate, delete the plugin via the plugin manager first. Then open the plugins folder (wp-content/plugins) via FTP and make sure that the “ajax-search-pro” and the “ajax-search-pro2” folders are deleted.
Wordpress probably no longer had access and was unable to delete the old plugin folder. It happens when the folder permissions were changed or the apache www-data process permissions are denied from the folder.
After deleting the folders, you should be able to install the plugin again, and it should work correctly. If not, then the “ajax-search-pro” folder was still not deleted due to permission issue. In this case you might have to connect to your server via SSH and set the permissions, or contact your server administrator to remove the folders securely.Best,
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