Hibernate @ManyToMany не заполняется таблица @JoinTable

Есть две таблицы children и section

Пытаюсь настроить отношение ManyToMany таблицы children и section заполняются но таблица child_section которая является JoinTable всегда пустая.

При попытке получить children из Section через запрос Section section = session.get(Section.class,2); Получаю только экземпляр Section без children

Возможно ошибка описана где то тут

Hibernate: insert into children (age, name) values (?, ?)
Hibernate: insert into children (age, name) values (?, ?)
Hibernate: insert into children (age, name) values (?, ?)
мая 01, 2022 7:28:30 PM org.hibernate.engine.jdbc.connections.internal.DriverManagerConnectionProviderImpl$PoolState stop
INFO: HHH10001008: Cleaning up connection pool [jdbc:postgresql://localhost:5432/my_db]
Exception in thread "main" java.lang.IllegalStateException: Transaction already active
    at org.hibernate.engine.transaction.internal.TransactionImpl.begin(TransactionImpl.java:74)
    at org.hibernate.internal.AbstractSharedSessionContract.beginTransaction(AbstractSharedSessionContract.java:468)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at org.hibernate.context.internal.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:351)
    at jdk.proxy2/jdk.proxy2.$Proxy37.beginTransaction(Unknown Source)
    at hibernate.many_to_many.Test.main(Test.java:35)

import javax.persistence.*;
import java.util.ArrayList;
import java.util.List;

@Entity
@Table(name = "section")
public class Section {
    @Id
    @Column(name = "id", nullable = false)
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    @Column(name = "name")
    private String name;


    @ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JoinTable(name = "child_section",
            joinColumns = @JoinColumn(name = "section_id", referencedColumnName = "id"),
            inverseJoinColumns = @JoinColumn(name = "child_id", referencedColumnName = "id"))

    private List<Child> children;

    public List<Child> getChildren() {
        return children;
    }

    public void setChildren(List<Child> children) {
        this.children = children;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public Section() {
    }

    public Section(String name) {
        this.name = name;
    }
    public void addChildrenToSection(Child child){
        if (children == null){
            children = new ArrayList<>();
        }
        children.add(child);
    }

    @Override
    public String toString() {
        return "Section{" +
                "id=" + id +
                ", name='" + name + '\'' +
                '}'+"\n";
    }
}

import javax.persistence.*;
import javax.persistence.GenerationType;
import java.util.ArrayList;
import java.util.List;

@Entity
@Table(name = "children")
public class Child {
    @Id
    @Column(name = "id", nullable = false)
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private int id;
    @Column(name = "name")
    private String firstName;
    @Column(name = "age")
    private int age;


    @ManyToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
    @JoinTable(name = "child_section",
            joinColumns = @JoinColumn(name = "child_id", referencedColumnName = "id"),
            inverseJoinColumns = @JoinColumn(name = "section_id", referencedColumnName = "id"))

    private List<Section> sections;

    public List<Section> getSections() {
        return sections;
    }

    public void setSections(List<Section> sections) {
        this.sections = sections;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public Child() {
    }

    public Child(String firstName, int age) {
        this.firstName = firstName;
        this.age = age;
    }

    @Override
    public String toString() {
        return "Child{" +
                "id=" + id +
                ", firstName='" + firstName + '\'' +
                ", age=" + age +
                '}';
    }
    public void addSectionToChildren(Section section){
        if (sections ==null){
            sections = new ArrayList<>();
        }
        sections.add(section);
    }
}

Метод тестирования

import hibernate.many_to_many.entity.Child;
import hibernate.many_to_many.entity.Section;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class Test {
    public static void main(String[] args) {
        SessionFactory sessionFactory = new Configuration()
                .configure("hibernate.cfg.xml")
                .addAnnotatedClass(Child.class)
                .addAnnotatedClass(Section.class)
                .buildSessionFactory();

        Session session = null;

        try {         
            session = sessionFactory.getCurrentSession();

            session.beginTransaction();

            Section section = session.get(Section.class,2);
            System.out.println(section);
            System.out.println(section.getChildren());

            session.beginTransaction().commit();

        } finally {
            session.close();
            sessionFactory.close();

        }

    }
}