Update AISerpGenArticleJob.php

app/Jobs/AISerpGenArticleJob.php

@@ -30,10 +30,10 @@ public function __construct()
      */
     public function handle(): void
     {
-       $category = Category::orderByRaw('ISNULL(serp_at) DESC')
+        $category = Category::orderByRaw('CASE WHEN serp_at IS NULL THEN 1 ELSE 0 END DESC')
             ->orderBy('serp_at', 'asc')
             ->first();
-        
+
         $news_serp_result = GetNewsSerpTask::handle($category, 'US');
 
         if (is_null($news_serp_result)) {