title: "refusing to merge unrelated histories" failure while pulling to recovered repository
body: <p>I come up with a problem about Git push.</p>
  
  <p>It worked successfully before, but it failed this time. In the beginning, I am in my master <code>MINGW64 /d/javasoft/apache-tomcat-7.0.70/webapps/MyNote (master)</code>, and then,</p>
  
  <ul>
  <li>I use <code>git remote add origin</code> to relate my remote origin, but it alerts that <code>fatal: remote origin already exists.</code></li>
  <li>then, I use <code>git remote rm origin</code> (Someone told me to), and it's OK.</li>
  <li>then, I use <code>git remote add origin https://github.com/***/***.git</code> again. It's OK.</li>
  <li>then, I use <code>git push -u origin master</code> ( I tried <code>git push origin master</code>, but I lost my local whole <code>.git</code> for some reason before, so I guess it may be the first time to push, and I should add <code>-u</code> ). BUT, it alerts <code>error: failed to push some refs to 'https://github.com/***/***.git'</code></li>
  <li>then, someone told me that I should use <code>git pull origin master</code> before I use <code>push</code>, and I did as it. BUT, it alerted: <code>fatal: refusing to merge unrelated histories</code>.</li>
  <li>I found some answers in <em><a href="https://stackoverflow.com/questions/37937984/git-refusing-to-merge-unrelated-histories">Git refusing to merge unrelated histories on rebase</a></em>, but it seemed that it didn't work. In my issue, it alerted <code>fatal: Couldn't find remote ref –allow-unrelated-histories</code></li>
  </ul>
  
  <hr>
  
  <p>I really don't know how to do... I just want to push...</p>