diff --git a/laborious/workflows/sub_workflows/format_and_export_prediction.py b/laborious/workflows/sub_workflows/format_and_export_prediction.py
index a9cda2a..68552b2 100644
--- a/laborious/workflows/sub_workflows/format_and_export_prediction.py
+++ b/laborious/workflows/sub_workflows/format_and_export_prediction.py
@@ -198,7 +198,7 @@ class FormatAndExportPrediction:
                 'table_name': input_data['table_name'],
                 'data': prediction,
                 'timestamp_conversion': {'column': 'timestamp', 'format': DATETIME_FORMAT_WITH_TZ},
-                'on_conflict': input_data.get('on_conflict', 'replace'),
+                'on_conflict': input_data.get('on_conflict', 'error'),
                 'unique_columns': ['model_id', 'timestamp'],
             },
             retry_policy=retry_policy,