I have a problem with testing adding user with password encoder

I have a problem when testing a method with using passwordencoder:

Cannot invoke "org.springframework.security.crypto.password.PasswordEncoder.encode(java.lang.CharSequence)" because the return value of "com.store.restAPI.user.UserConfig.passwordEncoder()" is null`

Thats my test class method:

    @ExtendWith(MockitoExtension.class)
    class UserServiceTest {

        private UserService underTest;
        @Mock
        private  UserRepository userRepository;
        @Mock
        private  UserConfig userConfig;

        @BeforeEach
        void setUp(){
            underTest = new UserService(userRepository, userConfig);
        }

        @Test
        void itShouldFindAllUsers() {
            //when
            underTest.findAll();

            //then
            verify(userRepository).findAll();

        }

        @Test
        void addNewUser() {
            //given
            User expected = new User(
                    "[email protected]",
                    "123"
            );

            //when
            underTest.addNewUser(expected);

            //then
            ArgumentCaptor<User> userArgumentCaptor = 
    ArgumentCaptor.forClass(User.class);
            verify(userRepository).save(userArgumentCaptor.capture());
            User capturedUser = userArgumentCaptor.getValue();
            assertThat(capturedUser).isEqualTo(expected);
        }

        @Test
        @Disabled
        void loginUser() {
        }
    }

And thats UserService method that i want to test:

    @Service
    public class UserService {

        private final UserRepository userRepository;
        private final UserConfig userConfig;

        @Autowired
        public UserService(UserRepository userRepository, UserConfig userConfig) {
            this.userRepository = userRepository;
            this.userConfig = userConfig;
        }

        public List<User> findAll() {
            return userRepository.findAll();
        }

        public void addNewUser(User user) {
            Optional<User> userOptional = userRepository.findUserByEmail(user.getEmail());
            if(userOptional.isPresent()){
                throw new IllegalStateException("email taken");
            }
            String hashedPassword = userConfig.passwordEncoder().encode(user.getPassword());
            user.setPassword(hashedPassword);
            userRepository.save(user);
        }

        public void loginUser(User user){
            Optional<User> userOptional = userRepository.findUserByEmail(user.getEmail());
            if(userOptional.isEmpty()){
                throw new IllegalStateException("no account under that email");
            }
            else 
    if(!userConfig.passwordEncoder().matches(user.getPassword(), 
    userOptional.get().getPassword())){
                throw new IllegalStateException("wrong password");
            }
        
    //!userOptional.get().getPassword().equals(user.getPassword())
         }
    }

Password encoder is a bean in class UserConfig.

    @Configuration
    public class UserConfig {

        @Bean
        CommandLineRunner commandLineRunnerUser(UserRepository repository) {
            return args -> {
                User iza = new User(
                        "[email protected]",
                    
    "$2a$10$U87IFlm9DYXRITUSnfdfDuknz8ijJCcK9UVR4D4kUDu7w13zPuURK"
                );

                User andrzej = new User(
                        "[email protected]",
                    
    "$2a$10$fmYOxyvWBr47wAg1m/ryy.G4J1PbT2LRj6m7oENkBtEsGocansE9G"
                );

                User tomek = new User(
                        "[email protected]",
                    
    "$2a$10$chrySvbZSZcje4r3Q0PZv.FrO6/k2WvM42GX3x2EmySZc/dAA2glC"
                );

                repository.saveAll(
                        List.of(iza,andrzej,tomek)
                );
            };
        }

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

Do i need to create another method with password encoder inside my test class? I don't know what am i doing wrong. Why does it say that result is null? Does someone know what am i doing wrong?