How to Fix Firebase invalid API key

Question

I'm using my API key stored in a .env.local file. And it setup correctly but not working

assert.ts:128 Uncaught FirebaseError: Firebase: Error (auth/invalid-api-key).
    at createErrorInternal (assert.ts:128:1)
    at _assert (assert.ts:153:1)
    at register.ts:67:1
    at Component.instanceFactory (register.ts:90:1)
    at Provider.getOrInitializeService (provider.ts:318:1)
    at Provider.initialize (provider.ts:242:1)
    at initializeAuth (initialize.ts:66:1)
    at getAuth (index.ts:44:1)
    at Module../src/firebase.init.js (firebase.init.js:22:1)
    at Module.options.factory (react refresh:6:1)

I don't know why React is giving me an error. I intialized firebase in the following file

// Import the functions you need from the SDKs you need
import { initializeApp } from "firebase/app";
import { getAuth } from "firebase/auth";
// TODO: Add SDKs for Firebase products that you want to use
// https://firebase.google.com/docs/web/setup#available-libraries

// Your web app's Firebase configuration
// For Firebase JS SDK v7.20.0 and later, measurementId is optional
const firebaseConfig = {
  
  apiKey: process.env.REACT_APP_apiKey,
  authDomain: process.env.REACT_APP_authDomain,
  projectId: process.env.REACT_APP_projectId,
  storageBucket: process.env.REACT_APP_storageBucket,
  messagingSenderId: process.env.REACT_APP_messagingSenderId,
  appId: process.env.REACT_APP_appId,
  measurementId:process.env.REACT_APP_measurementId
};

// Initialize Firebase
const app = initializeApp(firebaseConfig);
const auth = getAuth(app);
export default auth;