What exception to throw when you get 500 response code

Question

I want to know what type of exception to throw when I get 500 response code. I have my code something like

_logger is Microsoft.Extensions.Logging

HttpResponseMessage response = await Something.configureAwait(false);

if(response.IsSuccessStatusCode)
{
  //do something as it is 200 response
}
else if(response.StatusCode == HttpStatusCode.InternalServerError || response.StatusCode == HttpStatusCode.RequestTimeOut)
{
   _logger.LogError(response.StatusCode + "some Message");
  throw new HttpResponseException //error : type or namespace could not be found
} 
else
{
   _logger.LogError(response.StatusCode + "some Message");
  //Any other error code it means, there is something wrong in my code like 400, 404 (I passed incorrect url), 203 (again my issue).
}

I just want the user to retry if it is 500 and for the other cases, I would take care with unit test. Any suggestion is welcomed.