diff --git a/tests/Helper/SampleDataGenerator/GenerateSampleCategory.php b/tests/Helper/SampleDataGenerator/GenerateSampleCategory.php
index 887f34c1..71fadb0d 100644
--- a/tests/Helper/SampleDataGenerator/GenerateSampleCategory.php
+++ b/tests/Helper/SampleDataGenerator/GenerateSampleCategory.php
@@ -39,7 +39,11 @@ public function generateSampleCategories(string $blog_id, $parent_id = 0, int $n
       $errors = $categories_model->validate($insert_data, $data);
 
       if (count($errors) > 0) {
-        if (/*"Same name exists in the same hierarchy"*/"同一階層に同じ名前が存在しています" === ($errors['name'] ?? false)) {
+        // if set same category name (because low randomness) continue.
+        if (
+          "Same name exists in the same hierarchy" === ($errors['name'] ?? false) ||
+          "同一階層に同じ名前が存在しています" === ($errors['name'] ?? false)
+        ) {
           continue;
         }