Webhook Integration in C#

I have implemented webhook for revenuecat  in .net core C#. But for some reason I am getting 400 badrequest with empty response. I am mostly sure that I am not getting the json response in webook through revenuecat for any of the event occurring.
I have also added endpoint on revenue cat webhook with authentication. I have tried several time and as I have not way to test this on local machine. I need help from revenue cat team to provide some reference doc with sample implementation just to get proper json response. Below is the code snippet that I am using to get json response from the webhook endpoint added in revenuecat.

 

 var webHookSecret = _configuration[Constants.RevenueCatWebHookSecret];
                var headerAuthorization = HttpContext.Request.Headers["Authorization"].ToString();

                #region Check authorization
                if (webHookSecret == headerAuthorization)
                {
                    json = await new StreamReader(HttpContext.Request.Body).ReadToEndAsync();
                }
                else
                {
                    _logger.Information($"Un-Authorized token access in revenuecat webhook. Returning BadRequest response.");
                    throw new APIException(HttpStatusCode.Unauthorized, new APIError(_configuration, "InternalServerError"));
                }