public IActionResult Get(int pageNumber = 1, int pageSize = 50)
 {
     try
     {
         var pagination = new PagingParameter {
             PageSize = pageSize, PageNumber = pageNumber
         };
         var result = _useCaseFactory.GetContactsUseCase().Execute(pagination);
         Response.Headers.Add("Pagination", JsonConvert.SerializeObject(result.Pagination));
         return(Ok(result.Contacts));
     }
     catch (Exception e)
     {
         return(StatusCode(StatusCodes.Status500InternalServerError, e));
     }
 }