The toggler button is dropping down the list but it is not collapsing the list

I have copied every links which I have to. Also, copied the same code for the toggler which is in the bootstrap v5.1. The menu opens when I click on the toggler but it does not collapse if I click on it again. The code is working fine in bootstrap document but not in browser. Below is my code.

<html>
 <head> 
  <title>Toggler</title>   
  <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/css/bootstrap.min.css" 
   rel="stylesheet" integrity="sha384- 
   1BmE4kWBq78iYhFldvKuhfTAU6auU8tT94WrHftjDbrCEXSU1oBoqyl2QvZ6jIW3" crossorigin="anonymous">
 
  <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/js/bootstrap.bundle.min.js" 
   integrity="sha384-ka7Sk0Gln4gmtz2MlQnikT1wXgYsOg+OMhuP+IlRH9sENBO0LRn5q+8nbTov4+1p" 
   crossorigin="anonymous"></script>  
  <script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.10.2/dist/umd/popper.min.js" 
   integrity="sha384-7+zCNj/IqJ95wo16oMtfsKbZ9ccEh31eOz1HGyDuCQ6wgnyJNSYdrPa03rtR1zdB" 
   crossorigin="anonymous"></script>
  <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.1.3/dist/js/bootstrap.min.js" 
   integrity="sha384-QJHtvGhmr9XOIpI6YVutG+2QOK9T+ZnN4kzFN1RtK3zEFEIsxhlmWl5/YESvpZ13" 
   crossorigin="anonymous"></script>     
 </head>
 <body>
  <nav class="navbar navbar-expand-lg navbar-light bg-light">
   <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs- 
     target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria- 
     expanded="false" 
     aria-label="Toggle navigation">
     <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarSupportedContent">
      <ul class="navbar-nav me-auto mb-2 mb-lg-0">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
         <a class="nav-link" href="#">Link</a>
        </li>
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data- 
           bs- 
           toggle="dropdown" aria-expanded="false">
            Dropdown
          </a>
         <ul class="dropdown-menu" aria-labelledby="navbarDropdown">
          <li><a class="dropdown-item" href="#">Action</a></li>
          <li><a class="dropdown-item" href="#">Another action</a></li>
          <li><hr class="dropdown-divider"></li>
          <li><a class="dropdown-item" href="#">Something else here</a></li>
         </ul>
        </li>
        <li class="nav-item">
         <a class="nav-link disabled">Disabled</a>
        </li>
       </ul>
       <form class="d-flex">
        <input class="form-control me-2" type="search" placeholder="Search" aria- 
         label="Search">
        <button class="btn btn-outline-success" type="submit">Search</button>
       </form>
      </div>
     </div>
    </nav>   
   </body> 
  </html>