The historical execution of Dags is known as the backfilling in Airflow. By default the catchup will be in enabled which in turn lead to backfill.
To disable this, we need to set "catchup=False" in Dag configuration.
Example is sharing here for reference.
dag = DAG('Testdag', schedule_interval="30 4 * * *", default_args=default_args, dagrun_timeout=timedelta(minutes=3),catchup=False)
Here "catchup=False" is set in the argument field.