Code:
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Select active users from AD:");
            using (var context = new PrincipalContext(ContextType.Domain, "mydomain.com.nt", "OU=Departments,DC=com,DC=nt"))
            {   
                DirectoryEntry ldapConnection = new DirectoryEntry("LDAP://mydomain.com.nt/OU=Departments,DC=or,DC=nt",
...