public interface PersonRepository extends MongoRepository<Person, String> {
    Person findByName(String name);
}

public interface PhonebookRepository extends MongoRepository<Phonebook, String> {

        Phonebook findByNumer(String numer);
        Phonebook deleteByNumer(String numer);
    }

@Document(collection = "Person")
public class Person {
    @Id
    private String id;

    private String name;
    private String email;
    private String password;
    private String old;

    public Person(String name, String password) {
        this.name = name;
        this.email = email;
        this.password = password;
        this.old = old;
    }

@Document(collection = "Phonebook")
public class Phonebook {
    @Id
    private String id;

    private String date;
    private String numer;
    private String name;
    private String info;

    public Phonebook(String numer) {
        this.date = date;
        this.numer = numer;
        this.name = name;
        this.info = info;
    }