Not Able To place Trade In Banknifty Via API

I am getting the following message when I am trying to place order to banknifty: {‘status’: ‘error’, ‘errors’: [{‘errorCode’: ‘UDAPI100500’, ‘message’: ‘Market orders are not allowed on stock options. Place a limit order instead.’, ‘propertyPath’: None, ‘invalidValue’: None, ‘error_code’: ‘UDAPI100500’, ‘property_path’: None, ‘invalid_value’: None}]} This is the instrument_key = NSE_FO|67535