What is it and what to do with it?

Question

JavaScript

Tell me, please, how to fix it?
[Browsersync] 1 file changed (main.min.js)
[20:09:04] Finished 'scripts' after 2.8 s
[20:09:04] 'browsersync' errored after 2.87 s
[20:09:04] Error: listen EADDRINUSE: address already in use :::3005
at Server.setupListenHandle [as _listen2] (net.js:1313:16)
at listenInCluster (net.js:1361:12)
at Server.listen (net.js:1447: 7)
at module.exports.plugin (C:\Users\user\Desktop\mavik\node_modules\browser-sync\dist\server\index.js:27:25)
at Object.startServer [as fn] (C:\ Users\user\Desktop\mavik\node_modules\browser-sync\dist\async.js:179:52)
at C:\Users\user\Desktop\mavik\node_modules\browser-sync\dist\browser-sync.js: 120:14
at iterate (C:\Users\user\Desktop\mavik\node_modules\browser-sync\dist\utils.js:268:9)
at C:\Users\user\Desktop\mavik\node_modules\browser-sync\dist\ utils.js:279:21
at executeTask (C:\Users\user\Desktop\mavik\node_modules\browser-sync\dist\browser-sync.js:136:13)
at Object.mergeMiddlewares [as fn] (C: \Users\user\Desktop\mavik\node_modules\browser-sync\dist\async.js:168:9)
[20:09:04] 'default' errored after 2.88 s

const { src, dest, watch, parallel } = require('gulp');

const scss = require('gulp-sass');
const concat = require('gulp-concat');
const autoprefixer = require('gulp-autoprefixer');
const uglify = require('gulp-uglify');
const browserSync = require('browser-sync').create();
const imagemin = require('gulp-imagemin');



function browsersync() {
    browserSync.init({
        server: {
            baseDir: 'app/'
        }
    })
}

function styles() {
    return src('app/scss/style.scss')
        .pipe(scss({ outputStyle: 'compressed' }))
        .pipe(concat('style.min.css'))
        .pipe(autoprefixer({
            overrideBrowserslist: ['last 10 versions'],
            grid: true
        }))
        .pipe(dest('app/css'))
        .pipe(browserSync.stream())
}

function images() {
    return src('app/images/**/*.*')
        .pipe(imagemin([
            imagemin.gifsicle({ interlaced: true }),
            imagemin.mozjpeg({ quality: 75, progressive: true }),
            imagemin.optipng({ optimizationLevel: 5 }),
            imagemin.svgo({
                plugins: [
                    { removeViewBox: true },
                    { cleanupIDs: false }
                ]
            })
        ]))
        .pipe(dest('dist/images'))
}

function scripts() {
    return src([
        'node_modules/jquery/dist/jquery.js',
        'app/js/main.js'
    ])
        .pipe(concat('main.min.js'))
        .pipe(uglify())
        .pipe(dest('app/js'))
        .pipe(browserSync.stream())
}

function build(){
    return src([
        'app/**/*.html',
        'app/css/style.min.css',
        'app/js/main.min.js',
    ], {base:'app'})
    .pipe(dest('dist'))
}

function watching() {
    watch(['app/scss/**/*.scss'], styles);
    watch(['app/js/**/*.js', '!app/js/main.min.js'], scripts);
    watch(['app/*.html'], done => {
        browserSync.reload();
        done();
    });

}

exports.build = build;
exports.styles = styles;
exports.scripts = scripts;
exports.browsersync = browsersync;
exports.watching = watching;
exports.images = images;
exports.default = parallel(styles, scripts, browsersync, watching);

Answer 1

Writes that the address is already in use.
Simply put, you are trying to run browsersync a second time without terminating 1 process.
You may have already run it through another terminal.

Answer 2

It writes ([20:09:04] Error: listen EADDRINUSE: address already in use :::3005) that port 3005 is already in use, run on another port.