Сортировка по имени выдает ошибку

Хочу отсортировать по имени но выдает ошибку

public class Customer<T> {
    T id;
    String LastName;
    String FirstName;
    String Patronimic;
    String Adress;
    long phone;
    long nr;
    long sc;

    public Customer(T id, String LastName, String FirstName, String Patronimic, String Addres, long phone, long nr, long sc) {
        this.id = id;
        this.LastName = LastName;
        this.FirstName = FirstName;
        this.Patronimic = Patronimic;
        this.Adress = Addres;
        this.phone = phone;
        this.nr = nr;
        this.sc = sc;
    }
}

public class Main {
    public static void main(String[] args) {
        ArrayList<Customer> customers = new ArrayList<Customer>();
        customers.add(new Customer(1, "gyfgyg", "ufugfu", "jurghrb", "gbvjhrgu", 65265, 14514, 4415));
        customers.add(new Customer(2, "bfhgbfh", "ehbfh", "bhgbfh", "beshbdchb", 2052526125, 5020505, 515414));
        customers.add(new Customer("3", "vvgyv", "huhef", "ggbrf", "gygvg", 5151541, 4415114, 11541541));
        customers.add(new Customer("4", "fjnrgjnj", "fbehgbfhv", "begfyh", "fgbehfb", 0210515, 151, 201521025));

        Collections.sort(customers, cust.FirstName);
        for (Customer cust : customers) {
            System.out.println(cust.FirstName);
        }
    }
}

В чем ошибка?