Consider defining a bean of type 'service' in your configuration [Spring boot]

I get error when I run the main class.

Error:

Action:
Consider defining a bean of type 'seconds47.service.TopicService' in your configuration.

Description:
Field topicService in seconds47.restAPI.topics required a bean of type 'seconds47.service.TopicService' that could not be found

TopicService interface:

public interface TopicService {

    TopicBean findById(long id);

    TopicBean findByName(String name);

    void saveTopic(TopicBean topicBean);

    void updateTopic(TopicBean topicBean);

    void deleteTopicById(long id);

    List<TopicBean> findAllTopics(); 

    void deleteAllTopics();

    public boolean isTopicExist(TopicBean topicBean);
}

controller:

@RestController
public class topics {

    @Autowired
    private TopicService topicService;

    @RequestMapping(path = "/new_topic2", method = RequestMethod.GET)
    public void new_topic() throws Exception {
        System.out.println("new topic JAVA2");
    }
}

Implementation class:

public class TopicServiceImplementation implements TopicService {

    @Autowired
    private TopicService topicService;

    @Autowired
    private TopicRepository topicRepository;

    @Override
    public TopicBean findById(long id) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public TopicBean findByName(String name) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public void saveTopic(TopicBean topicBean) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public void updateTopic(TopicBean topicBean) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public void deleteTopicById(long id) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public List<TopicBean> findAllTopics() {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public void deleteAllTopics() {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public boolean isTopicExist(TopicBean topicBean) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }
}

Rest of the classes are defined too. I don't know why its throwing despite declaring componentScan in main class.

Main class:

@SpringBootApplication(exclude = {SecurityAutoConfiguration.class })
@ComponentScan(basePackages = {"seconds47"})
@EnableJpaRepositories("seconds47.repository")
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

I have my packages like this:

seconds47
seconds47.beans
seconds47.config
seconds47.repository
seconds47.restAPI
seconds47.service