redis-adapter is not getting Socket:client object when I run more than one replica in a docker compose yml

[harsoz]

This is my docker-compose:

services:
chat-api:
build: .
ports:
- "3004-3006:3005"
depends_on:
- redis
environment:
CHAT_GATEWAY_REDIS_URL: redis://redis:6379
CHAT_GATEWAY_PORT: "3005"
CHAT_REDIS_CACHE_HOST: redis
CHAT_REDIS_CACHE_PORT: 6379
CHAT_REDIS_QUEUE_HOST: redis
CHAT_REDIS_QUEUE_PORT: 6379
deploy:
replicas: 2
restart: on-failure

redis:
image: redis
ports:
- "6379:6379"
deploy:
replicas: 1

and my redis adapter, taken from NestJs doc:

import { IoAdapter } from "@nestjs/platform-socket.io";
import { ServerOptions } from "socket.io";
import { createAdapter } from "@socket.io/redis-adapter";
import { createClient } from "redis";

export class RedisAdapter extends IoAdapter {
private adapterConstructor: ReturnType;

async connectToRedis(): Promise {
const pubClient = createClient({
url: process.env.CHAT_GATEWAY_REDIS_URL || redis://localhost:6379,
});
const subClient = pubClient.duplicate();

await Promise.all([pubClient.connect(), subClient.connect()]);

this.adapterConstructor = createAdapter(pubClient, subClient);

}

createIOServer(port: number, options?: ServerOptions): any {
const server = super.createIOServer(port, options);
server.adapter(this.adapterConstructor);
return server;
}
}

The problem is that, when I use more than one replica, sometimes, the socket which is connected (or tries to connect) is null or undefined, so I cannot perform operations.
Maybe I'm missing something.