Improve Accessibility of Audio Content with the audio Element !PLEASE HELP!

Tell us what’s happening:
I don’t understand what I have done wrong, I thought I did what it asked me to, but I still have one thing I need to do. It says: Cannot read property ‘length’ of null

Your code so far

    <h1>Real Coding Ninjas</h1>
    <p>A sound clip of Zersiax's screen reader in action.</p>
    <audio id="" controls>
      <source src=""
type="audio/mpeg" />

Your browser information:

User Agent is: Mozilla/5.0 (X11; CrOS x86_64 10575.55.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.87 Safari/537.36.

Link to the challenge:

Your <audio> tag is missing it’s closing tag: </audio>.
Place the closing tag after the <source> tag.

Thank you so much!!!