Hibernate update fails during test run with Spock, but succeeded in debug mode

Hibernate update fails during test run with Spock, but succeeded in debug
("Evaluate code fragment" mode).

ERROR: duplicate key value violates unique constraint "category_pkey" Detail: Key (id)=(1) already exists.

Latest libraries.

What is wrong?

How fix it?

class Test extends BaseSpecification {
private static final long one = 1L
private static final long two = 2L
private static final String name = "NAME"
private CategorySqlHibernateDAO target
@Shared
private Category firstCategory = new Category(id: one, name: name)
@Shared
private Category secondCategory = new Category(id: two, name: name, parent: firstCategory)

void setup() {
    add(firstCategory)
    target = getBean(CategorySqlHibernateDAO)
}

def "Save"() {// ---------------------- FAILED -----------------------------
    target.save(this.secondCategory)

    expect:
    assertTable(firstCategory, secondCategory)
}//...
}

BaseSpecification

abstract class BaseSpecification extends Specification {
protected Sql sql
protected final ApplicationContext context = new ClassPathXmlApplicationContext("contexts/dao-beans.xml")

protected initialize() {
    sql = new Sql(context.getBean(DataSource))
    truncate()
}

protected boolean truncate() {
    sql.execute("TRUNCATE TABLE " + modelClass.simpleName)
}

protected void add(Object... records) {
    initialize()
    if (specificationContext.currentIteration.name.toUpperCase().contains("SAVE")) {
         sql.dataSet(modelClass).add(ObjectUtility.asMap(records[0]))
    } else {
        records.each { sql.dataSet(modelClass).add(ObjectUtility.asMap(it)) }
    }
}

CategorySqlHibernateDAO

public class CategorySqlHibernateDAO extends HibernateDaoSupport {
@Transactional
public Serializable save(Entity entity) {
    return getHibernateTemplate().save(entity);
}
}

Category

@Entity
@Table(indexes = {
    @Index(name = "nameIndex", columnList = "name")})
@JsonInclude(JsonInclude.Include.NON_DEFAULT)
public class Category implements NamedModel {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private long id;
@NotNull
@Column(length = 256)
@Size(min = 1, max = 256)
private String name;
@JoinColumn(name = "parentId")
@OneToOne(fetch = FetchType.EAGER)
@JsonInclude(JsonInclude.Include.NON_NULL)
private Category parent;
@JsonIgnore
@JsonInclude(JsonInclude.Include.NON_EMPTY)
@OneToMany(cascade = {CascadeType.REMOVE}, orphanRemoval = true, fetch = FetchType.LAZY, mappedBy = "parent")
private List<Category> children;
}