[Spring Data] Не работает кастомная Query

public interface PlaylistDao extends JpaRepository<Playlist, Long>{
    Playlist findByLink(String link);
    Playlist findById(long id);
 
    Set<Playlist> findAllByUsers(User user);
    Set<Playlist> findAllBySubject(Subject subject);
 
    @Query("SELECT Subject FROM Playlist p WHERE p.id = (:id)")
    Subject findSubjectOfThePlaylist(@Param("id") long id);
}

@Entity
@Table(name = "playlists")
public class Playlist {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;
 
    @Column(name = "name")
    private String name;
 
    @Column(name = "channel")
    private String channel;
 
    @Column(name = "link")
    private String link;
 
    @Column(name = "amount_of_completed_videos")
    private int amountOfCompletedVideos = 0;
 
    @Column(name = "amount_of_videos")
    private int amountOfVideos;
 
    @ManyToMany(mappedBy = "playlists")
    private Set<User> users;
 
    @OneToMany(fetch = FetchType.LAZY, mappedBy = "playlist")
    private Set<Video> videos = new HashSet<>();
 
    @ManyToOne(cascade = CascadeType.ALL, fetch = FetchType.LAZY)
    @JoinColumn(name = "subject_id", nullable = false)
    private Subject subject;
 
    public Playlist() {
    }
 
    public Playlist(String name, String channel, String link, Set<User> users) {
        this.name = name;
        this.channel = channel;
        this.link = link;
        this.users = users;
    }
 
    public Playlist(String name, String channel, String link, int amountOfVideos) {
        this.name = name;
        this.channel = channel;
        this.link = link;
        this.amountOfVideos = amountOfVideos;
    }
 
    //getters-setters

@Entity
@Table(name = "subjects")
public class Subject {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;
 
    @Column(name = "title")
    private String title;
 
    @ManyToOne(cascade = CascadeType.ALL, fetch = FetchType.LAZY)
    @JoinColumn(name = "user_id", nullable = false)
    private User user;
 
    @OneToMany(mappedBy = "subject")
    private Set<Playlist> playlists;
 
    public Subject() {
    }
 
    public Subject(String title, User user) {
        this.title = title;
        this.user = user;
    }
 
    //getters-setters
}