Error: Timeout of 2000ms exceeded. For async tests and hooks, ensure "done()" is called;

Tried timeout and done() function to solve this problem but it is not working showing Error: Timeout of 2000ms exceeded. For async tests and hooks, ensure "done()" is called; error.

Controller

var plan_details = require('../../models/plan_details');
module.exports = function () {
return {
    getPlansList: function (request, callback) {
        plan_details.find().sort({ createdAt: -1 }).exec().then((result) => {
            log.info("Getting All Plan Details");
            callback({ status: 200, success: true, result: result });
        }).catch(err => {
            log.error("Getting error while getting all plans");
            log.error(err);
            callback({ status: 400, success: false, message: "Unable to 
            Process your Request" });
        });
    }
 }}

Test case

var expect = require("chai").expect;
var request = require("request");
var PlanMgmnt = require('../routes/PlanManagement/PlanManagement')();

describe("--Plan Management API", function () {
describe("--Add Plan API", function () {
    it("--returns status 200", function (done) {
        PlanMgmnt.getPlansList({}, function(res){
            console.log(res);
        });
        // done();
    });
});});

It not printing the res in console.log.