CLosedXML.Report plugin Generates report, but main Program hangs

Question

i have Revit Plugin that is made of a ribbon solution that calls a functio to generate a report using ClosedXML.Report. When i run the code, there are no errors and the the Excel File is generated properly with the correct data in it. However, my Revit program hangs. If i comment out the "template.Generate" line in my code, Revit does not hang. I am not sure how to debug it.

Here is my code:

    public void CreateReport()
        {
List<order> orders1 = new List<order>()
{
    new order() {
        OrderNo = 1001,
        SaleDate = new DateTime(2024, 3, 15),
        ShipDate = new DateTime(2024, 3, 20),
        ShipToAddr1 = "123 Main St",
        ShipToAddr2 = "Apt 101",
        PaymentMethod = "Credit",
        ItemsTotal = 50.0,
        TaxRate = 0.1,
        AmountPaid = 55.0
    },
    new order() {
        OrderNo = 1002,
        SaleDate = new DateTime(2024, 3, 18),
        ShipDate = new DateTime(2024, 3, 23),
        ShipToAddr1 = "456 Elm St",
        ShipToAddr2 = "Suite 200",
        PaymentMethod = "Cash",
        ItemsTotal = 75.0,
        TaxRate = 0.05,
        AmountPaid = 78.75
    }
};

// Specify INput and output file names
const string templateFile = @"Z:\BIM\405_Industrial\2024_2_26\Templates\customerTest.xlsm"; string outputFile = @"Z:\BIM\405_Industrial\2024_2_26\Output\customerTest.xlsm";

            // Add Data to cust object
            CustomerTest cust = new CustomerTest(orders1);

            // Create a new ClosedXML.Report object
            var template = new XLTemplate(templateFile);
            
             // Add the data to the template Object
             template.AddVariable(cust);

            // Generate the template into the excel workbook
            template.Generate();

            //Save the Workbook
            template.Workbook.SaveAs(outputFile);
        } // CreateReport

Any ideas on how to resolve this?