Express+mongodb cannot return data from the database

let express = require("express");
let router = express.Router();
let mongoose = require("mongoose");
let Notices = require("../models/notices");

//MongoDB
mongoose.connect("mongodb://127.0.0.1:27017/chm",{ useNewUrlParser: true });
// mongoose.connect("mongodb://root:123456@127.0.0.1:27017/park");

mongoose.connection.on("connected", function() {
  console.log("MongoDB connected success.");
});

mongoose.connection.on("error", function() {
  console.log("MongoDB connected fail.");
});

mongoose.connection.on("disconnected", function() {
  console.log("MongoDB connected disconnected.");
});
router.get("/", function(req, res, next) {
  // res.send("Hello, notices list.");
  console.log(Notices);
  Notices.find({}, function (err, doc) {
    if(err) {
      res.json({
        status: "1",
        msg: err.message
      });
    } else {
      console.log()
      res.json({
        status:"0",
        msg: "",
        result: {
          count: doc.length,
          list: doc
        }
      })
    }
  });
});

module.exports = router;

cannot get the returned doc when running. I don"t know what went wrong

Oct.25,2021
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