public async Task <ActionResult> Delete(string identifier)
        {
            try {
                bool result = await actionFactory
                              .CreateDeleteChargeAction()
                              .Execute(identifier);

                if (result)
                {
                    return(Ok());
                }
                else
                {
                    return(NotFound());
                }
            }
            catch (ChargesException ex) {
                return(BadRequest(ex.Message));
            }
        }