Can each service in a docker-compose file have their own mongo instance?

In this case I have two services and their respective database

version: '3.8'

services:
  authentication:
    build:
      context: ./authentication
      dockerfile: dockerfile
    environment:
      PORT: 3001
      DB_PORT: 27017
      DB_NAME: authenticationdatabase
      DB_USER: username
      DB_PASSWORD: password
      SIGNATURE_KEY: DITMOETGEINJECTEERDWORDEN
    volumes:
      - ./authentication:/authentication
    ports:
      - 3001:3001

  authenticationdatabase:
    image: mongo:latest
    environment:
      - MONGO_INITDB_DATABASE=authenticationdatabase
      - MONGO_INITDB_ROOT_USERNAME=username
      - MONGO_INITDB_ROOT_PASSWORD=password
    ports:
      - 27017:27017
    restart: always
    volumes:
      - authentication_db_volume:/data/authentication

  hosting:
    build:
      context: ./hosting
      dockerfile: dockerfile
    environment:
      PORT: 3002
      DB_PORT: 27017
      DB_NAME: hostingdb
      DB_USER: username
      DB_PASSWORD: password
      CLOUDINARY_URL: ${CLOUDINARY_URL}
      JWT_SIGNATURE_KEY: DITMOETGEINJECTEERDWORDEN
    volumes:
      - ./hosting:/hosting
    ports:
      - 3002:3002
    restart: always
    depends_on:
      - hostingdb

  hostingdb:
    image: mongo:latest
    environment:
      - MONGO_INITDB_DATABASE=hostingdb
      - MONGO_INITDB_ROOT_USERNAME=username
      - MONGO_INITDB_ROOT_PASSWORD=password
    ports:
      - 27018:27017
    restart: always
    volumes:
      - hostingdb_volume:/data/hosting
volumes:
  authentication_db_volume:
  hostingdb_volume:

Running this docker-compose file works perfectly, and both instances of mongodb run on their respective ports: both mongodb instances

The issue comes from when one of the services connects with mongodb through mongoose, for example here is authentication service connecting with authenticationdatabase:

Error connecting to MongoDB: MongooseServerSelectionError: connection timed out
  at NativeConnection.Connection.openUri (/authentication/node_modules/mongoose/lib/connection.js:825:32)
  at /authentication/node_modules/mongoose/lib/index.js:414:10
  at /authentication/node_modules/mongoose/lib/helpers/promiseOrCallback.js:41:5
  at new Promise (<anonymous>)
  at promiseOrCallback (/authentication/node_modules/mongoose/lib/helpers/promiseOrCallback.js:40:10)
  at Mongoose._promiseOrCallback (/authentication/node_modules/mongoose/lib/index.js:1288:10)
  at Mongoose.connect (/authentication/node_modules/mongoose/lib/index.js:413:20)
  at Object.<anonymous> (/authentication/services/mongoose.js:27:10)
  at Module._compile (internal/modules/cjs/loader.js:1114:14)
  at Object.Module._extensions..js (internal/modules/cjs/loader.js:1143:10) {
reason: TopologyDescription {
  type: 'Unknown',
  servers: Map(1) { 'authenticationdatabase:27017' => [ServerDescription] },
  stale: false,
  compatible: true,
  heartbeatFrequencyMS: 10000,
  localThresholdMS: 15,
  setName: null,
  maxElectionId: null,
  maxSetVersion: null,
  commonWireVersion: 0,
  logicalSessionTimeoutMinutes: null
},
code: undefined

And finally here is the connector for mongoose:

const mongoose = require('mongoose');
const connectionString = `mongodb://${process.env.DB_USER}:${process.env.DB_PASSWORD}@${process.env.DB_NAME}:${process.env.DB_PORT}`;


// Set up Mongoose connection event listeners
const db = mongoose.connection;
mongoose.set('strictQuery', false)
db.set('strictQuery', false);
db.on('connecting', () => {
  console.log('Connecting to MongoDB...');
});

db.on('connected', () => {
  console.log('Connected to MongoDB');
});

db.on('error', (error) => {
  console.error('Error connecting to MongoDB:', error);
  process.exit(1); // Exit the process if there is an error connecting to the database
});

db.on('disconnected', () => {
  console.log('Disconnected from MongoDB');
});

// Connect to MongoDB
mongoose.connect(connectionString);

module.exports = db;

Running each service individually works perfectly fine, but combined causes a port block or something else which I can't see or find. Please help.

Tried port fixing with the docker command expose, or inserting the mongo command so that it listens to different ports, unsuccesful

My solution came from building a better dependency when building. Allowing the secondary mongo image to wait for the previous database before building solved my issue. Also in docker-desktop running the first database, then the service, allowing those to connect then repeat for the second database and service. This worked perfectly, so use those depends_on