An error occured while attempting to process /ajax/ajax_facets/refresh:$.blockUI is not a function

Ajax facets work but I get an error “An error occured while attempting to process /ajax/ajax_facets/refresh:$ .blockUI is not a function” when I click on ajax links with checkboxes for the facets for the first time.

I am using search api views as per mentioned in the project description You can check the error in the screenshot attached enter image description here