spring cloud api gateway connection timed out - microservices

Question

I have the following setup:
eureka server
api gateway
auth service
Api gateway yml:
server:
port: 8081
spring:
application:
name: api-gateway
zipkin:
base-url: http://localhost:9411
cloud:
gateway:
discovery:
locator:
enabled: true
lower-case-service-id: true
routes:
- id: auth
uri: lb://auth
predicates:
- Path=/api/user/**
eureka:
client:
service-url:
defaultZone: http://localhost:8761/eureka
fetch-registry: true
register-with-eureka: true
instance:
prefer-ip-address: true
hostname: localhost
Auth service yml:
server:
port: 8080
spring:
application:
name: auth
eureka:
client:
service-url:
defaultZone: http://localhost:8761/eureka
fetch-registry: true
register-with-eureka: true
instance:
prefer-ip-address: true
hostname: localhost
On the eureka web dashboard both services are showing correctly. Now, I want to test the auth service with the endpoint /api/user/signup.
If I fire a post request like this:
http://localhost:8081/auth/api/user/signup
or like this:
http://localhost:8081/api/user/signup
Before adding
instance:
prefer-ip-address: true
hostname: localhost
I got an unknown host exception, how I get this:
io.netty.channel.AbstractChannel$AnnotatedConnectException: Connection timed out: no further information: /192.168.0.104:8080
I'm currently at home, but router and wifi works. But indeed, if I copy in the browser the 192.168.0.104, then I get connection timeout.
I'm developing this app on a company laptop (which has it's own domain), and which I use at home on my own network. Maybe this can be relevant. Basically I just want to use localhost. But how?