Code is not submitting even i have written correct

Tell us what’s happening:
Describe your issue in detail here.

  **Your code so far**
/* file: index.html */
<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Balance Sheet</title>
  <link rel="stylesheet" href="./styles.css">
</head>
<body>
  <main>
    <section>
      <h1>
        <span class="flex">
          <span>AcmeWidgetCorp</span>
          <span>Balance Sheet</span>
        </span>
      </h1>
      <div id="years" aria-hidden="true">
        <span class="year">2019</span>
        <span class="year">2020</span>
        <span class="year">2021</span>
      </div>
      <div class="table-wrap">
        <table>
          <caption>Assets</caption>
          <thead>
            <tr>
              <td></td>
              <th>
                <span class="sr-only year">2019</span>
              </th>
              <th>
                <span class="sr-only year">2020</span>
              </th>
              <th>
                <span  class="sr-only year current">2021</span>
              </th>
            </tr>
          </thead>
          <tbody>
          </tbody>
        </table>
        <table>
        </table>
        <table>
        </table>
      </div>
    </section>
  </main>
</body>
</html>
/* file: styles.css */

  **Your browser information:**

User Agent is: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/102.0.5005.115 Safari/537.36 OPR/88.0.4412.53

Challenge: Step 11

Link to the challenge:

Hello!

Take a look at the task:

Give your third th element the class attribute set to current .

Not span.