title: Ambiguous use of DispatchQueue on trying to use main thread
body: <p>This is a weird issue and I can't seem to find any help. On Swift 3, trying to make a call on the main thread I try to use DispatchQueue.main.async, but it doesn't compile.</p>
  
  <p>Any ideas would be helpful. </p>
  
  <p><a href="https://i.stack.imgur.com/0yw6Z.png" rel="noreferrer"><img src="https://i.stack.imgur.com/0yw6Z.png" alt="enter image description here"></a></p>