diff --git a/greg/tests/models/test_scheduletask.py b/greg/tests/models/test_scheduletask.py
index 37765c773be08fa322f8fa0668035eb86c01a5a1..5b2e199d6ec0609c88700fbe12d057d6163d0746 100644
--- a/greg/tests/models/test_scheduletask.py
+++ b/greg/tests/models/test_scheduletask.py
@@ -5,7 +5,7 @@ from greg.models import ScheduleTask
 
 @pytest.fixture
 def scheduletask():
-    ScheduleTask.objects.create(name="foo", last_completed="2020-10-15 23:04")
+    ScheduleTask.objects.create(name="foo", last_completed="2020-10-15T23:04Z")
     return ScheduleTask.objects.get(id=1)