404 not found in RestController in Spring Boot

I have a Spring Boot Project with pom.xml like this

<groupId>com.project</groupId>
    <artifactId>prj</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>prj</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.11</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

The Application class is like this

@SpringBootApplication
public class PrjApplication {

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

And I have a RestController where I am trying to do some CRUD Operations like this

@RestController("/register")
public class RegisterController {
    @Autowired
    private UserRepository userRepository;

    @GetMapping("/user/{id}")
    public User getUser(@Valid @RequestBody Long id){
        User user = userRepository.getOne(id);
        return user;
    }

    @PostMapping("/new")
    public User saveUser(@Valid @RequestBody String name,@Valid @RequestBody String email,@Valid @RequestBody String password,@Valid @RequestBody String phone){
        System.out.println("savginv user");
        User user = new User();
        user.setEmail(email);
        user.setPassword(password);
        user.setName(name);
        user.setPhone(phone);
        userRepository.save(user);
        return user;
    }
}

I have made an Entity class; User like this

@Entity
@Table(name = "tbl_users")
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    Long id;

    String name, email, password, phone;

    public Long getId() {
        return id;
    }



    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }
}

When I try to save a user by calling the post method using PostMan it gives me 404 not found error.

{
    "timestamp": "2018-06-23T06:47:14.086+0000",
    "status": 404,
    "error": "Not Found",
    "message": "No message available",
    "path": "/prj/register/new"
}

I am using JPARepository to perform Database operations.