diff --git a/.github/workflows/assign-reviewer.yml b/.github/workflows/assign-reviewer.yml
index 2bf910e..0b64dc4 100644
--- a/.github/workflows/assign-reviewer.yml
+++ b/.github/workflows/assign-reviewer.yml
@@ -2,7 +2,7 @@ name: Assign Unique Reviewer
 
 on:
   pull_request:
-    types: [opened, synchronize]
+    types: [opened]
 
 permissions:
   issues: write