Mongoose document expires too quickly

Question

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

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("Article", articleSchema);

export default Article;