C# create datatable from a list

I am working on re-writing my code to use SqlBulkCopy Class to test the insert record performance. I am running into errors converting List to a DataTable.

public string toTbl(IList < string > records) {
    const string connectionString = @ "Data Source=sqlserver;Initial Catalog=dbname;User Id=user;Password=password;";    
    try {
        var studentData = from record in records
        let srec = record.Split(',')
        select new Student {
            ID = srec[0],
            Student = srec[1],
            Grade = srec[2]
        };

        foreach(var i in studentData) {
            using(SqlConnection sqlConnection = new SqlConnection(connectionString)) {
                sqlConnection.Open();    
                using(SqlCommand cmd = new SqlCommand("INSERT INTO [Student] ([ID], [Student], [Grade]) VALUES (@ID, @Student, @Grade)", sqlConnection)) {
                    cmd.Parameters.AddWithValue("@ID", i.ID);
                    cmd.Parameters.AddWithValue("@Student", i.Student);
                    cmd.Parameters.AddWithValue("@Grade", i.Grade);    
                    cmd.ExecuteNonQuery();
                }
                sqlConnection.Close();
            }
        }
    } catch (Exception ex) {
        message = ex.Message;
    }
}

private string toTbl(IList < string > records)
        {
            const string connectionString = @ "Data Source=sqlserver;Initial Catalog=dbname;User Id=user;Password=password;"; 
            try
            {               
                ListtoDataTable lsttodt = new ListtoDataTable();
                DataTable dt = lsttodt.ToDataTable(records);

                using (var conn = new SqlConnection(connectionString))
                {
                    await conn.OpenAsync();
                    using (var bulkCopy = new SqlBulkCopy(conn))
                    {
                        bulkCopy.DestinationTableName = "Student";

                        try
                        {
                            // Write from the source to the destination.
                            await bulkCopy.WriteToServerAsync(dt);
                        }
                        catch (Exception ex)
                        {
                            Console.WriteLine(ex.Message);
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            return (null);
        }

        public class ListtoDataTable
        {
            public DataTable ToDataTable<T>(List<T> items)
            {
                DataTable dataTable = new DataTable(typeof(T).Name);
                //Get all the properties by using reflection   
                PropertyInfo[] Props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);
                foreach (PropertyInfo prop in Props)
                {
                    //Setting column names as Property names  
                    dataTable.Columns.Add(prop.Name);
                }
                foreach (T item in items)
                {
                    var values = new object[Props.Length];
                    for (int i = 0; i < Props.Length; i++)
                    {

                        values[i] = Props[i].GetValue(item, null);
                    }
                    dataTable.Rows.Add(values);
                }

                return dataTable;
            }
        }