diff --git a/combo/main.py b/combo/main.py
index b8130746a4a4829643e9d4a70c70d133ddb6ede6..699abb2d1b51d89ef8fe5a6b3100dd29a51f334c 100755
--- a/combo/main.py
+++ b/combo/main.py
@@ -304,7 +304,7 @@ def set_seed(seed: int) -> None:
 
 def run(_):
 
-    if FLAGS.seed:
+    if FLAGS.seed is not None:
         set_seed(FLAGS.seed)
 
     if FLAGS.mode == 'train':