c# LINQ to XML null value exception

This is my code:

List<Customer> customersList =
                (
                    from e in XDocument.Load(file).Root.Elements("cust")
                    select new Customer
                    {
                        CustomerID = (int)e.Element("custid"),
                        FirstName = (string)e.Element("fname"),
                        LastName = (string)e.Element("lname"),
                        ShowsNumber = (int)e.Element("count_noshow"),
                        VisitNumber = (int)e.Element("count_resos"),
                        Cancellation = (int)e.Element("count_cancel"),
                    }).ToList();

I got {"Value cannot be null.\r\nParameter name: element"} exception on the customerList = (....) part of the code,

I can see the XML, it has a lot of cust nodes under the root node.

could you help me please?

Many thanks Best regards,