diff --git a/mcserver/views.py b/mcserver/views.py
index 417a870..7384a89 100644
--- a/mcserver/views.py
+++ b/mcserver/views.py
@@ -441,7 +441,9 @@ def permanent_remove(self, request, pk):
 
             session = get_object_or_404(Session, pk=pk, user=request.user)
             self.check_object_permissions(self.request, session)
-            session.delete()
+            # Delete all non-calibration trials. We keep the session itself to avoid breaking the chain of sessions.
+            Trial.objects.filter(session=session).exclude(name="calibration").delete()
+            # session.delete()
         except Http404:
             if settings.DEBUG:
                 raise APIException(_("error") % {"error_message": str(traceback.format_exc())})