diff --git a/nodeconductor/logging/tasks.py b/nodeconductor/logging/tasks.py
index <HASH>..<HASH> 100644
--- a/nodeconductor/logging/tasks.py
+++ b/nodeconductor/logging/tasks.py
@@ -1,9 +1,8 @@
-import uuid
 import logging
 
 from celery import shared_task
-from datetime import datetime
 from django.conf import settings
+from django.utils import timezone
 
 from nodeconductor.logging.loggers import event_logger
 from nodeconductor.logging.models import BaseHook, Alert
@@ -41,4 +40,4 @@ def close_alerts_without_scope():
 def alerts_cleanup():
     timespan = settings.NODECONDUCTOR.get('CLOSED_ALERTS_LIFETIME')
     if timespan:
-        Alert.objects.filter(is_closed=True, closed__lte=datetime.now() - timespan).delete()
+        Alert.objects.filter(is_closed=True, closed__lte=timezone.now() - timespan).delete()
Fix alerts cleanup (NC-<I>)