diff --git a/scripts/process-issues.py b/scripts/process-issues.py
index 620fb0b..96b8c88 100644
--- a/scripts/process-issues.py
+++ b/scripts/process-issues.py
@@ -103,7 +103,7 @@ def main():
                     continue
 
                 print(f">> Will tag issue #{issue_number} with '{stale_tag}'")
-                update_labels = list(update_labels | {stale_tag})
+                update_labels = list(update_labels | stale_tag)
 
 
         # --- Make update with new labels ---