Spring Boot Project with 404 Error

This is my controller

package com.iape.cobranca.resource;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.iape.cobranca.model.Conta;
import com.iape.cobranca.repository.ContaRepository;

@RestController
@RequestMapping("/contas")
public class ContaResource {

    @Autowired
    private ContaRepository contaRepository;

    @GetMapping
    public List<Conta> lista(){
        return contaRepository.findAll();
    }


}

This is my repository;

package com.iape.cobranca.repository;

import org.springframework.data.jpa.repository.JpaRepository;

import com.iape.cobranca.model.Conta;

public interface ContaRepository extends JpaRepository<Conta, Long> {

}

This is my entity;

package com.iape.cobranca.model;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "conta")
public class Conta {

    private Long codigo;
    private String nome;

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    public Long getCodigo() {
        return codigo;
    }

    public void setCodigo(Long codigo) {
        this.codigo = codigo;
    }

    public String getNome() {
        return nome;
    }

    public void setNome(String nome) {
        this.nome = nome;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((codigo == null) ? 0 : codigo.hashCode());
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        Conta other = (Conta) obj;
        if (codigo == null) {
            if (other.codigo != null)
                return false;
        } else if (!codigo.equals(other.codigo))
            return false;
        return true;
    }



}

This is my pom.xml file

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.iape.cobranca.api</groupId>
    <artifactId>cobranca</artifactId>
    <version>1.0.0-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>cobranca</name>
    <description></description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.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-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>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>


        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>

        <!-- Migracoes - Flyway -->
        <dependency>
            <groupId>org.flywaydb</groupId>
            <artifactId>flyway-core</artifactId>
        </dependency>
    </dependencies>

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



</project>

That's how I'm connecting to the bank;

spring.jpa.database=POSTGRESQL
spring.jpa.database-platform=org.hibernate.dialect.PostgreSQL9Dialect
spring.jpa.properties.hibernate.temp.use_jdbc_metadata_defaults = false


  spring.jpa.hibernate.ddl-auto=create

 spring.datasource.url=jdbc:postgresql://localhost:5432/boleto?createDatabaseIfNotExist=true&useSSL=false
 spring.datasource.username=postgres
 spring.datasource.password=postgres





   #server.port=8181

spring.jpa.show-sql=true


spring.jackson.deserialization.fail-on-unknown-properties=true

spring.jackson.date-format=yyyy-MM-dd

Why am I getting the 404 error?