diff --git a/app/jobs/0_xray_core.py b/app/jobs/0_xray_core.py
index 2a720dda5..3007cde25 100644
--- a/app/jobs/0_xray_core.py
+++ b/app/jobs/0_xray_core.py
@@ -59,7 +59,7 @@ def start_core():
     for node_id in node_ids:
         xray.operations.connect_node(node_id, config)
 
-    scheduler.add_job(core_health_check, 'interval', seconds=10, coalesce=True)
+    scheduler.add_job(core_health_check, 'interval', seconds=10, coalesce=True, max_instances=1)
 
 
 @app.on_event("shutdown")
diff --git a/app/jobs/record_usages.py b/app/jobs/record_usages.py
index 676f4fcf6..1a048b35c 100644
--- a/app/jobs/record_usages.py
+++ b/app/jobs/record_usages.py
@@ -195,5 +195,5 @@ def record_node_usages():
         record_node_stats(params, node_id)
 
 
-scheduler.add_job(record_user_usages, 'interval', coalesce=True, seconds=30)
-scheduler.add_job(record_node_usages, 'interval', coalesce=True, seconds=10)
+scheduler.add_job(record_user_usages, 'interval', coalesce=True, seconds=30, max_instances=1)
+scheduler.add_job(record_node_usages, 'interval', coalesce=True, seconds=10, max_instances=1)