Mocking fails for some reason

@Service
@Validated
public class UserService {

    private final UserRepository userRepository;
    private final BCryptPasswordEncoder passwordEncoder;

    public UserService(UserRepository userRepository, BCryptPasswordEncoder passwordEncoder) {
        this.userRepository = userRepository;
        this.passwordEncoder = passwordEncoder;
    }

    public Optional<User> getUserById(Long id) {
        return userRepository.findById(id);
    }

    /**
     * Saves a user to the database, the provided password should not
     * be handed as hashed, as it will be hashed automatically.
     * @param user User
     * @return User
     * @throws ConstraintViolationException When some of the fields are not valid
     */
    @Transactional
    public User save(@Valid User user) {
        user.setPassword(passwordEncoder.encode(user.getPassword()));
        return userRepository.save(user);
    }
}

@Service
@Validated
public class UserService {

    private final UserRepository userRepository;
    private final BCryptPasswordEncoder passwordEncoder;

    public UserService(UserRepository userRepository, BCryptPasswordEncoder passwordEncoder) {
        this.userRepository = userRepository;
        this.passwordEncoder = passwordEncoder;
    }

    public Optional<User> getUserById(Long id) {
        return userRepository.findById(id);
    }

    /**
     * Saves a user to the database, the provided password should not
     * be handed as hashed, as it will be hashed automatically.
     * @param user User
     * @return User
     * @throws ConstraintViolationException When some of the fields are not valid
     */
    @Transactional
    public User save(@Valid User user) {
        user.setPassword(passwordEncoder.encode(user.getPassword()));
        return userRepository.save(user);
    }
}

@ExtendWith(MockitoExtension.class)
class UserServiceTests {

    User testUser = new User(
            1L,
            "xxxJohnxxx",
            "John Doe",
            "[email protected]",
            "Password123"
    );

    @Mock
    UserRepository userRepository;

    @Autowired
    @InjectMocks
    UserService userService;

    @BeforeEach
    void setUp() {
        when(userRepository.findById(1L)).thenReturn(Optional.of(testUser));
        when(userRepository.findById(2L)).thenReturn(Optional.empty());
    }

    @Test
    void testFindUserById() {
        assertThat(userService.findUserById(1L)).hasValueSatisfying(usr -> {
            assertThat(usr.getUsername()).isEqualTo("xxxJohnxxx");
        });
        assertThat(userService.findUserById(2L)).isEmpty();
    }

    @Test
    void testFindUserByUsername() {
        when(userRepository.findByUsername("xxxJohnxxx")).thenReturn(Optional.of(testUser));
        assertThat(userService.findUserByUsername("xxxJohnxxx")).isNotEmpty();
        assertThat(userService.findUserByUsername("Johnxxx")).isEmpty();
    }

    @Test
    void testSave() {
        User userWrong = User.builder()
                .username("Johnxxx")
                .name("John Doe")
                .email("john.doe").password("Password1").build();
        User userCorrect = User.builder()
                .username("Johnxxx")
                .email("[email protected]").password("Password1").build();
        assertThatThrownBy(() -> userService.save(userWrong))
                .isInstanceOf(ConstraintViolationException.class);
        assertThat(userService.save(userCorrect)).isNotNull();
    }
}

@ExtendWith(MockitoExtension.class)
class UserServiceTests {

    User testUser = new User(
            1L,
            "xxxJohnxxx",
            "John Doe",
            "[email protected]",
            "Password123"
    );

    @Mock
    UserRepository userRepository;

    @Autowired
    @InjectMocks
    UserService userService;

    @BeforeEach
    void setUp() {
        when(userRepository.findById(1L)).thenReturn(Optional.of(testUser));
        when(userRepository.findById(2L)).thenReturn(Optional.empty());
    }

    @Test
    void testFindUserById() {
        assertThat(userService.findUserById(1L)).hasValueSatisfying(usr -> {
            assertThat(usr.getUsername()).isEqualTo("xxxJohnxxx");
        });
        assertThat(userService.findUserById(2L)).isEmpty();
    }

    @Test
    void testFindUserByUsername() {
        when(userRepository.findByUsername("xxxJohnxxx")).thenReturn(Optional.of(testUser));
        assertThat(userService.findUserByUsername("xxxJohnxxx")).isNotEmpty();
        assertThat(userService.findUserByUsername("Johnxxx")).isEmpty();
    }

    @Test
    void testSave() {
        User userWrong = User.builder()
                .username("Johnxxx")
                .name("John Doe")
                .email("john.doe").password("Password1").build();
        User userCorrect = User.builder()
                .username("Johnxxx")
                .email("[email protected]").password("Password1").build();
        assertThatThrownBy(() -> userService.save(userWrong))
                .isInstanceOf(ConstraintViolationException.class);
        assertThat(userService.save(userCorrect)).isNotNull();
    }
}

@Mock
PasswordEncoder passwordEncoder;

@Mock
PasswordEncoder passwordEncoder;

@Bean
public PasswordEncoder passwordEncoder() {
  return new BCryptPasswordEncoder();
}

@Bean
public PasswordEncoder passwordEncoder() {
  return new BCryptPasswordEncoder();
}

assertThatExceptionOfType(ConstraintViolationException.class)
  .isThrownBy(() -> ...);

assertThatExceptionOfType(ConstraintViolationException.class)
  .isThrownBy(() -> ...);