title: Git merge develop into feature branch outputs "Already up-to-date" while it's not
body: <p>I checked out a feature branch from develop called <code>branch-x</code>. After a while other people pushed changes to the develop branch. </p>
  
  <p>I want to merge those changes into my <code>branch-x</code>. However if I do </p>
  
  <pre><code>git merge develop 
  </code></pre>
  
  <p>it says "Already up-to-date" and doesn't allow me to merge. </p>
  
  <p><code>git diff develop</code> shows that there are differences between <code>branch-x</code> and develop.</p>
  
  <p>How do I merge develop into <code>branch-x</code>?</p>