React App cannot reach API container with fetch or axios [duplicate]

I have 2 docker containers, one running React App and the other one running Node Express API. Here is my docker-compose.yml file:

version: '3.8'

services:
  node-api:
    build: ./node-api
    ports:
      - 9000:9000
    restart: 
      on-failure

  react-app:
    build: ./react-app
    ports:
      - 3000:3000
    depends_on:
      - node-api

When I try calling an API with fetch, I get 'CORS request did not succeed' error. CORS is enabled on the backend:

const express = require("express");
const cors = require("cors");

const app = express();
app.use(cors());

Here is also a function inside React App that calls API:

const handleContentClick = async () => {
   let url = `http://node-api:9000/api/content`;
   const response = await fetch(url);
   const data = await response.json();
}

I tried explicitly setting CORS origin to react-app container, but that did not help.

One thing that confuses me is when I enter react-app container and try accessing an API with curl or node, I get the response from API. Why is it reachable from the same container via node and curl, but not from React App?

I also tried replacing fetch with axios, but I still got an error (this time it is ERR_NETWORK error).

Also, everything worked fine when I ran this on my local machine, but once I tried running it on a remote host, these errors appeared.

Do you have any suggestions?