我试图在5分钟后删除一个MongoDB文档，但它几乎在2分钟后删除。我真的不知道这个问题。我们非常感谢您的帮助。

const hospitalRecordSchema = new mongoose.Schema({
  hospital_id: {
    type: String,
  },
  hospital_name: {
    type: String,
  },
  created_at: {
    type: Date,
    default: new Date(),
    expires: "5m",
    index: true,
  },
  data: {
    type: Object,
    default: {},
  },
});

hospitalRecordSchema.index({ created_at: 1 }, { expireAfterSeconds: 300 });

module.exports = mongoose.model("HospitalRecord", hospitalRecordSchema);

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