Failed to load resource: the server responded with a status of 500 (Internal Server Error) - AJAX

Question

I have a controller named CustomersInfoAPIController. I'm using Knock out, webapi2, asp.net mvc5 to build an application. I'm binding the data using knout JS. When I run the application and debug the knockout script, I don't see any error .When I try to insert data using AJAX I see error `"Failed to load resource: the server responded with a status of 500 (Internal Server Error)"

the ajax code is:

 $.ajax({
            url: '/api/CustomersInfo',
            type: 'post',
            data: dataObject,
            contentType: 'application/json',
            success: function (data) {

    addCustomerViewModel.customerListViewModel.customers.push(new 
    Customer(data.Id,data.CustomerName, data.ContactName, data.Address,    
     data.City, data.PostalCode, data.Country));
                self.Id(null);
                self.CustomerName('');
                self.ContactName('');
                self.Address('');
                self.City('');
                self.PostalCode('');
                self.Country('');
            }
        });