ECONNREFUSED at TCPConnectWrap.afterConnect NodeJS - node.js

Question

i created a nodejs app which should use a URI to connect to rabbitmq. both are containerized with docker and are created by a docker-compose file. after running of "docker-compose up" the nodejs app returns an error:
Error: connect ECONNREFUSED X.X.X:X:5672
at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1133:16) {
errno: -111,
code: 'ECONNREFUSED',
syscall: 'connect',
address: '172.26.0.4',
port: 5672
}
when starting the api-server locally (not as a container-> as an node application), the connection to the containerized rabbitmq server estabilish without any problems.
my rabbitmq.conf file looks like:
default_vhost = /
default_user = guest
default_pass = guest
default_user_tags.administrator = true
default_permissions.configure = .*
default_permissions.read = .*
default_permissions.write = .*
loopback_users = none
listeners.tcp.default = 5672
management.listener.port = 15672
management.listener.ssl = false
management.load_definitions = /etc/rabbitmq/definitions.json
URI for connecting:
{
"mongoURI":"mongodb://mongo:27017",
"amqpURI": "amqp://guest:guest#rabbitmq:5672"
}
as you can see, the hostname is equal to the one, which is within the docker-compose file
finally the docker-compose file:
version: "3.8"
services:
react-app:
image: react-app
stdin_open: true
ports:
- "3000:3000"
networks:
- mern-app
api-server:
image: api-server
ports:
- "5000:5000"
networks:
- mern-app
depends_on:
- mongo
- rabbitmq
process-schedular:
image: process-schedular
ports:
- "5005:5005"
networks:
- mern-app
depends_on:
- mongo
- rabbitmq
mongo:
image: mongo:3.6.19-xenial
ports:
- "27017:27017"
networks:
- mern-app
volumes:
- mongo-data:/data/db
rabbitmq:
image: rabbitmq:3-management
hostname: rabbitmq
volumes:
- ./server/amqp/docker/enabled_plugins:/etc/rabbitmq/enabled_plugins
- ./server/amqp/docker/definitions.json:/etc/rabbitmq/definitions.json
- ./server/amqp/docker/rabbitmq.conf:/etc/rabbitmq/rabbitmq.conf
ports:
- "5672:5672"
- "15672:15672"
networks:
- mern-app
networks:
mern-app:
driver: bridge
volumes:
mongo-data:
driver: local