title: Mongoose document expires too quickly
body: <p>I want to have my articles deleted after an hour, as you can see from the code, but they are being deleted after about 2 minutes</p>
  <pre><code>import mongoose from 'mongoose';
  
  var articleSchema = new mongoose.Schema({
      title: String,
      text: String,
      link: String,
      description: String,
      imgLink: String,
      source: String,
  } , { timestamps: true }
  );
  
  articleSchema.index({ createdAt: 1 }, { expires: '60m' });
  
  var Article = mongoose.model(&quot;Article&quot;, articleSchema);
  
  export default Article;
  </code></pre>