Não preenche a tabela

Hibernate: 
    select
        nextval ('hibernate_sequence')
Hibernate: 
    insert 
    into
        Conta
        (agencia, banco, numero, titular, id) 
    values
        (?, ?, ?, ?, ?)

package br.com.marlon.teste;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;

import br.com.marlon.financas.Conta;

public class TesteConta {

    public static void main(String[] args) {

        Conta conta = new Conta();
        conta.setTitular("Marlon Mazzine");
        conta.setBanco("NuBank");
        conta.setAgencia("0001");
        conta.setNumero("12345678");

        EntityManagerFactory emf =  Persistence.createEntityManagerFactory("contas-postgres");
        EntityManager em = emf.createEntityManager();

        em.getTransaction().begin();
        em.persist(conta);
        em.getTransaction().commit();

        em.close();
        emf.close();
    }

}

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
    version="2.0">

    <persistence-unit name="contas-postgres">
        <provider>org.hibernate.ejb.HibernatePersistence</provider>
        <class>br.com.marlon.financas.Conta</class>
        <properties>
            <property name="javax.persistence.jdbc.driver" value="org.postgresql.Driver" />
            <property name="javax.persistence.jdbc.url" value="jdbc:postgresql://localhost/conta" />
            <property name="javax.persistence.jdbc.user" value="postgres" />
            <property name="javax.persistence.jdbc.password" value="1234" />

            <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
            <property name="hibernate.hbm2ddl.auto" value="update" />
            <property name="hibernate.show_sql" value="true" />
            <property name="hibernate.format_sql" value="true" />
        </properties>
    </persistence-unit>

</persistence>

package br.com.marlon.financas;

import javax.persistence.*;

@Entity
public class Conta {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;
    private String titular;
    private String numero;
    private String banco;
    private String agencia;

    public Integer getId() {
        return id;
    }

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

    public String getTitular() {
        return titular;
    }

    public void setTitular(String titular) {
        this.titular = titular;
    }

    public String getNumero() {
        return numero;
    }

    public void setNumero(String numero) {
        this.numero = numero;
    }

    public String getBanco() {
        return banco;
    }

    public void setBanco(String banco) {
        this.banco = banco;
    }

    public String getAgencia() {
        return agencia;
    }

    public void setAgencia(String agencia) {
        this.agencia = agencia;
    }
}