diff --git a/src/dispatch/signal/flows.py b/src/dispatch/signal/flows.py
index 7f39ce99dd86..9cc7706b7034 100644
--- a/src/dispatch/signal/flows.py
+++ b/src/dispatch/signal/flows.py
@@ -10,7 +10,7 @@ def create_signal_instance(db_session: SessionLocal, signal_instance_data: dict)
     """Creates a signal and a case if necessary."""
     signal = signal_service.get_by_variant_or_external_id(
         db_session=db_session,
-        external_id=signal_instance_data.external_id,
+        external_id=signal_instance_data.id,
         variant=signal_instance_data.variant,
     )
     signal_instance_in = SignalInstanceCreate(**signal_instance_data, project=signal.project)