diff --git a/posthog/warehouse/api/external_data_schema.py b/posthog/warehouse/api/external_data_schema.py
index 9ee1755ee922f..56208208d5eaf 100644
--- a/posthog/warehouse/api/external_data_schema.py
+++ b/posthog/warehouse/api/external_data_schema.py
@@ -141,6 +141,8 @@ def update(self, instance: ExternalDataSchema, validated_data: dict[str, Any]) -
             payload = instance.sync_type_config
             payload["incremental_field"] = data.get("incremental_field")
             payload["incremental_field_type"] = data.get("incremental_field_type")
+            payload["incremental_field_last_value"] = None
+            payload["incremental_field_last_value_v2"] = None
 
             validated_data["sync_type_config"] = payload
         else: