System.NullReferenceException: Object reference not set to an instance of an object.
at Dynamicweb.eCommerce.Products.Group.get_AllGroupsByLanguageID(String languageID)
at Dynamicweb.eCommerce.Products.Group.get_GroupByID(String groupID, String languageId, String defaultLanguageId)
at Dynamicweb.eCommerce.Frontend.Frontend.HandleFacetGroupResult(IQuery query, IFacetGroup facetGroup, FacetGroupResult facetGroupResult, IDictionary`2 parameters)
at Dynamicweb.eCommerce.Frontend.Frontend.GetProductsFromIndexQuery()