title: The type or namespace name 'UI' does not exist in the namespace 'UnityEngine'
body: <p>I am doing a small course for beginners about <code>Unity 3D</code> <a href="https://learn.unity.com/project/john-lemon-s-haunted-jaunt-3d-beginner" rel="nofollow noreferrer">here</a>. 
  After importing all the assets from the unity asset store, as explained in the course, I get an error that probably shouldn't be generated, that says:</p>
  
  <blockquote>
    <p>The type or namespace name '<em>UI</em>' does not exist in the namespace UnityEngine</p>
  </blockquote>
  
  <p>I have already searched for this problem but I have only found answers from older versions of Unity. I tried, as some said, to <strong>reimport all the assets</strong> and to <strong>close and re-open unity</strong> but both ways seem to not work for me.</p>
  
  <p>This is the first line of code from the ChinemachineStoryboard file, that the compiler indicates:
  <code>public UnityEngine.UI.RawImage mRawImage;</code></p>
  
  <p>The second one (line 32) is just a comment so i don't understand how it could affect anything, but just in case, here it is:
  <code>/// &lt;summary&gt;Image will be cropped if necessary so that the screen is entirely filled&lt;/summary&gt;</code></p>