Reactjs – Build fail to compile due to Unexpected end of JSON input

I have an issue when trying to build my react app.

This works perfectly in a dev environement using npm start however once I try to build it I have this error.

> [email protected] build
> react-scripts build

Creating an optimized production build...
Failed to compile.

Unexpected end of JSON input

I have added a console log to verify that my environment variables are correctly replaced in dev environment however those are not fetch correctly during the build.

My .env is at the root directory of my application and all my variable starts with REACT_APP_*

The code of the login page I am trying to build

import React, { useState } from "react";
import { signInWithEmailAndPassword } from "firebase/auth"; // Import signInWithEmailAndPassword
import { auth } from "./firebase"; // Import Firebase auth instance

function Login() {
  const [email, setEmail] = useState("");
  const [password, setPassword] = useState("");
  const [error, setError] = useState("");

  const handleSubmit = async (event) => {
    event.preventDefault();

    if (!email || !password) {
      setError("Email and password are required.");
      return;
    }

    try {
      const userCredential = await signInWithEmailAndPassword(auth, email, password);
      console.log("User signed in:", userCredential.user);
      alert("Login successful!");
    } catch (err) {
      console.error("Error during login:", err.message);
      setError("Login failed: " + err.message);
    }
  };

  return (
    <div>
      <h1>Login</h1>
      <form onSubmit={handleSubmit}>
        <div>
          <label>Email:</label>
          <input
            type="email"
            value={email}
            onChange={(e) => setEmail(e.target.value)}
            required
          />
        </div>
        <div>
          <label>Password:</label>
          <input
            type="password"
            value={password}
            onChange={(e) => setPassword(e.target.value)}
            required
          />
        </div>
        {error && <p style={{ color: "red" }}>{error}</p>}
        <button type="submit">Login</button>
      </form>
    </div>
  );
}

export default Login;

Thanks