diff --git a/aleksis/core/models.py b/aleksis/core/models.py
index d1641fa09633564823e7af604f6b7be02ad0d7cb..b0cbc0c09af83511c1bd10cba2f297897ae16046 100644
--- a/aleksis/core/models.py
+++ b/aleksis/core/models.py
@@ -1934,6 +1934,10 @@ class CalendarEvent(
 
             self.rrule_until = rule.until
         else:
+            self.rrule = None
+            self.rrule_until = None
+            self.exdatetimes = []
+            self.rdatetimes = []
             self.timezone = None
 
         super().save(*args, **kwargs)