I create a file in task, then use bulk_load to load it into the database. The code is executed without errors, but nothing appears in the database, what could be the problem?

Code that I think doesn’t work:

path = r'/opt/airflow/dags/asd/data/'
 with open(os.path.join(path+"{}.csv".format(get_dates())), 'w+', encoding='utf-8') as f:
      f.write(resultcsv)               
      fname = f.name
      try:

         hook = PostgresHook(postgres_conn_id='test_db')                   
         hook.bulk_load('testdb', fname)
      finally:           
         os.remove(fname)

airflow log:

{postgres.py:168} INFO - Running copy expert: COPY testdb FROM STDIN, filename: /opt/airflow/dags/asd/data/2024-08-15.csv
{base.py:73} INFO - Using connection ID 'test_db' for task execution.
{python.py:194} INFO - Done. Returned value was: None
{taskinstance.py:1400} INFO - Marking task as SUCCESS.
{local_task_job_runner.py:228} INFO - Task exited with return code 0

I tried saving the file in different formats: csv and tsv, but it didn’t work