diff --git a/app/Controller/admin/api/KeywordsController.php b/app/Controller/admin/api/KeywordsController.php
index 8ec6478..5cae168 100644
--- a/app/Controller/admin/api/KeywordsController.php
+++ b/app/Controller/admin/api/KeywordsController.php
@@ -72,7 +72,7 @@ class KeywordsController extends AbstractController
 
         $query->keyword = $keyword;
 
-        $ignoreUrl = array_filter(array_unique(explode(PHP_EOL, $ignoreUrl ?: [])));
+        $ignoreUrl = array_filter(array_unique(explode(PHP_EOL, $ignoreUrl ?: '')));
         $query->ignore_url = json_encode($ignoreUrl);
         $query->save();