问实体错误的映射中的另一个重复列

EN

Here the error :
SEVERE: Exception while invoking class org.glassfish.persistence.jpa.JPADeployer
prepare method
SEVERE: Exception while preparing the app
SEVERE: [PersistenceUnit: supmarket] Unable to build EntityManagerFactory

...

Caused by: org.hibernate.MappingException: Repeated column in mapping for entity:
com.supmarket.entity.Sale column: customerId
(should be mapped with insert="false" update="false")

@Entity
public class Sale {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @Column(nullable=false)
    private Long idFromAgency;

    private float amountSold;

    private String agency;

    @Temporal(javax.persistence.TemporalType.DATE)
    private Date createdate;

    @Column(nullable=false)
    private Long productId;

    @Column(nullable=false)
    private Long customerId;

    @ManyToOne(optional=false)
    @JoinColumn(name="productId",referencedColumnName="id_product")
    private Product product;

    @ManyToOne(optional=false)
    @JoinColumn(name="customerId",referencedColumnName="id_customer")
    private Customer customer;


    public void Sale(){}    
    public void Sale(Long idFromAgency, float amountSold, String agency
            , Date createDate, Long productId, Long customerId){        
        ...
    }

    // then getters/setters
}

@Entity
public class Customer {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name="id_customer")
    private Long id_customer;

    @Column(nullable=false)
    private Long idFromAgency;

    private String  gender,
                    maritalState,
                    firstname,
                    lastname,
                    incomeLevel;

    @OneToMany(mappedBy="customer",targetEntity=Sale.class, fetch=FetchType.EAGER)
    private Collection sales;


    public void Customer(){}

    public void Customer(Long idFromAgency, String gender, String maritalState,
            String firstname, String lastname, String incomeLevel) {
        ...
    }

}

public class Product {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name="id_product")
    private Long id_product;

    @Column(nullable=false)
    private Long idFromAgency;

    private String name;

    @OneToMany(mappedBy="product",targetEntity=Sale.class, fetch=FetchType.EAGER)
    private Collection sales;

    //constructors + getters +setters
}