diff --git a/pyinjective/async_client.py b/pyinjective/async_client.py
index 327aedb0..43f3818c 100644
--- a/pyinjective/async_client.py
+++ b/pyinjective/async_client.py
@@ -141,7 +141,7 @@ def __init__(
         )
 
         # timeout height update routine
-        aiocron.crontab(
+        self.cron = aiocron.crontab(
             '* * * * * */{}'.format(DEFAULT_TIMEOUTHEIGHT_SYNC_INTERVAL),
             func=self.sync_timeout_height,
             args=(),