I have followed this tutorial to make a hamburger menu in react/next.js: https://youtu.be/prbOI7G0RvY

import { useState } from "react";
import user from '../styles/userview.module.css'

export function PageHeader() {

  const [isOpen, setIsOpen] = useState(false);
  const openMenu= ()=> setIsOpen(!isOpen);

  return (
    <header className={user.header}>
    <nav className={user.navbar}>
        <a className={user.navlogo}>[BrandLogo]</a>
      <ul className={isOpen === false ?
          user.navmenu : user.navmenu + ' ' + user.active}>
        <li className={user.navitem}>
            <a className={user.navlink}>Home</a>
        </li>
        <li className={user.navitem}>
          
            <a className={user.navlink}>About</a>
   
        </li>
        <li className={user.navitem}>
       
            <a className={user.navlink}>Contact</a>
  
        </li>
      </ul>
      <button className={isOpen === false ? user.hamburger : user.hamburger + ' ' + user.active}
                          onClick= {openMenu}
                          >
        <span className={user.bar}></span>
        <span className={user.bar}></span>
        <span className={user.bar}></span>
      </button>
    </nav>
  </header>
  )
}

But I keep getting this error message:

Error: Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen for one of the following reasons:

1. You might have mismatching versions of React and the renderer (such as React DOM)
2. You might be breaking the Rules of Hooks
3. You might have more than one copy of React in the same app See https://reactjs.org/link/invalid-hook-call for tips about how to debug and fix this problem.

It also indicates the problem is at this row: const [isOpen, setIsOpen] = useState(false);

Can someone please help me to understand what is wrong?

EDIT: Here is a picture of the exact error message: https://pasteboard.co/3xyAu6m8IeAW.png

EDIT 2: I opened up my repo so you can see/test it on your own. Maybe the fault is in another file? The burgermenu is in the main-branch and ..components/userview and the page that imports and show the burgermenu is ../pages/hamburgertestfile.