Spring Boot - problem przy zapisaniu rekordu do reposytorium JPA

Parameter value [5] did not match expected type [web.javaLearn.model.course.Course (n/a)]

@Data
@Entity
@Builder
public class Page {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String name;
    private Float pageOrder;
    @Enumerated(EnumType.STRING)
    private PageType type;
    private String data;

    @ManyToOne(cascade = CascadeType.ALL)
    private Course course;
}

@Data
@Entity
@Builder
@AllArgsConstructor
@NoArgsConstructor
public class Course {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String title;
    private String description;

    @OneToMany(cascade = CascadeType.ALL, mappedBy = "course")
    List<Page> pageList;
}

@Repository
public interface PageRepository extends JpaRepository<Page, Long> {
    @Query(value = "SELECT * FROM page WHERE course_id = ?1 ORDER BY page_order", nativeQuery = true)
    List<Page> findAllPagesByCourse(Long courseId);

    Page findFirstByCourseOrderByPageOrderDesc(Long courseId);
}

@Transactional
    public Page savePage(PageRequest pageRequest, Long courseId) {
        Course c = courseRepository.findById(courseId).orElseThrow();
        Page p = Page.builder()
                .name(pageRequest.getName())
                .pageOrder(pageRepository.findFirstByCourseOrderByPageOrderDesc(courseId).getPageOrder()+1)
                .type(pageRequest.getType())
                .data(pageRequest.getData())
                .course(c)
                .build();
        pageRepository.save(p);
        return p;
    }

@Transactional
public Page savePage(PageRequest pageRequest, Long courseId) {
courseRepository.findById(courseId)
.map(course -> course.addPeage(Page.builder...itd.))
.orElseThrow()
}