Fix

app/Repositories/Shop/Articles.php

@@ -32,7 +32,7 @@ class Articles
     {
         $articles = Article::with(['article_nature'])->get();
         foreach ($articles as $article) {
-            $data[$article->id] = $article->article_nature->name . ' - ' . $article->name;
+            $data[$article->id] = ($article->article_nature->name ?? null) . ' - ' . $article->name;
         }
         asort($data, SORT_NATURAL);
         return $data;