Spring Boot apps deployed on Heroku are not properly registered with Eureka

I have several Spring Boot apps deployed to Heroku. I have the following services registered with Eureka:

• configserver
• eureka-server
• gateway
• uaa
  The configserver, gateway and uaa registers themselves, but it registers itself with Eureka but not rightly. When I executed the request to the gateway (POST https://APP_NAME.herokuapp.com/auth/login), the response is Uaa service 503 Service Unavailable.

Gateway Log:

- heroku[router]: at=error code=H12 desc="Request timeout" method=POST path="/auth/login"
    
- DynamicServerListLoadBalancer for client uaa initialized:
  DynamicServerListLoadBalancer:{NFLoadBalancer:name=uaa,current list
  of Servers=[IP_ADDRESS:PORT],Load balancer stats=Zone stats:
  {defaultzone=[Zone:defaultzone;	Instance count:1;	Active connections
  count: 0;	Circuit breaker tripped count: 0;	Active connections per
  server: 0.0;]
    
- Server stats: [[Server:IP_ADDRESS:PORT;	Zone:defaultZone;	Total
  Requests:0;	Successive connection failure:0;	Total blackout
  seconds:0;	Last connection made:Thu Jan 01 00:00:00 UTC 1970;	First
  connection made: Thu Jan 01 00:00:00 UTC 1970;	Active
  Connections:0;	total failure count in last (1000) msecs:0;	average
  resp time:0.0;	90 percentile resp time:0.0;	95 percentile resp
  time:0.0;	min resp time:0.0;	max resp time:0.0;	stddev resp time:0.0]

This is my configuration for Eureka-server:
application-prod.yml

eureka:
  instance:
    hostname: ${DOMAIN_NAME}
    status-page-url-path: ${management.endpoints.web.base-path}/info
    health-check-url-path: ${management.endpoints.web.base-path}/health
    lease-renewal-interval-in-seconds: 5
    lease-expiration-duration-in-seconds: 10
    metadata-map:
      profile: ${spring.profiles.active}
      version: #project.version#
      git-version: ${git.commit.id.describe:}
      git-commit: ${git.commit.id.abbrev:}
      git-branch: ${git.branch:}
  client:
    fetch-registry: false
    register-with-eureka: false
    instance-info-replication-interval-seconds: 10
    registry-fetch-interval-seconds: 10
    service-url:
      defaultZone: http://admin:${spring.security.user.password}@${eureka.instance.hostname}:${server.port}/eureka/

This is my configuration for Uaa:
application-prod.yml

eureka:
  client:
    service-url:
      defaultZone: ${application.register.discovery-url}/eureka/
    instance-info-replication-interval-seconds: 10
    registry-fetch-interval-seconds: 10
  instance:
    hostname: ${DOMAIN_NAME:localhost}
    appname: uaa
    prefer-ip-address: true
    instanceId: uaa:${spring.application.instance-id:${random.value}}
    status-page-url-path: ${management.endpoints.web.base-path}/info
    health-check-url-path: ${management.endpoints.web.base-path}/health
    lease-renewal-interval-in-seconds: 5
    lease-expiration-duration-in-seconds: 10
    metadata-map:
      profile: ${spring.profiles.active}
      version: #project.version#
      git-version: ${git.commit.id.describe:}
      git-commit: ${git.commit.id.abbrev:}
      git-branch: ${git.branch:}

This is my configuration for Gateway:
application-prod.yml

eureka:
  client:
    service-url:
      defaultZone: ${application.register.discovery-url}/eureka/
    instance-info-replication-interval-seconds: 10
    registry-fetch-interval-seconds: 10
  instance:
    hostname: ${DOMAIN_NAME:localhost}
    appname: gateway
    prefer-ip-address: true
    instance-id: gateway:${spring.application.instance-id:${random.value}}
    status-page-url-path: ${management.endpoints.web.base-path}/info
    health-check-url-path: ${management.endpoints.web.base-path}/health
    lease-renewal-interval-in-seconds: 5
    lease-expiration-duration-in-seconds: 10
    metadata-map:
      profile: ${spring.profiles.active}
      version: #project.version#
      git-version: ${git.commit.id.describe:}
      git-commit: ${git.commit.id.abbrev:}
      git-branch: ${git.branch:}

POM all services:
Eureka clients and server:

<parent>
 <groupId>org.springframework.boot</groupId>
 <artifactId>spring-boot-starter-parent</artifactId>
 <version>2.2.6.RELEASE</version>
 <relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
 <java.version>1.8</java.version>
 <spring-cloud.version>Hoxton.SR4</spring-cloud.version>
 </properties>
<dependency>
 <groupId>org.springframework.cloud</groupId>
 <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>

<dependencyManagement>
 <dependencies>
  <dependency>
	<groupId>org.springframework.cloud</groupId>
	<artifactId>spring-cloud-dependencies</artifactId>
	<version>${spring-cloud.version}</version>
	<type>pom</type>
	<scope>import</scope>
   </dependency>
 </dependencies>
</dependencyManagement>

Only Eureka server:

<dependency>
 <groupId>org.springframework.cloud</groupId>
 <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>

Uaa and gateway connection was never established, I guess the problem is when registering eureka-clients with eureka. Also I have try modifing this property eureka.instance.prefer-ip-address: false and the eureka-clients are registers as APP_NAME.herokuapp.com:PORT which makes it either non-discoverable or unable to lookup or call other registered services.

NOTE:

All service alrady registered with eureka server

eureka.instance.prefer-ip-address: false
list of Servers=[APP_NAME.herokuapp.com:PORT] of ribbon.

eureka.instance.prefer-ip-address: true
list of Servers=[IP_ADDRESS:PORT] of ribbon

DOMAIN_NAME = APP_NAME.herokuapp.com for all services.

I execute ping to IP_ADDRESS and no response

I have Use Account Heroku for test.