실시간데이터베이스에 안떠요..6:15초

6분15초에서 하는 list를 누르면 파이어베이스에 뭔가 생기는데 저는 안생겨요..이렇게 생기지 않습니다.....

package com.bokchi.mysolelife.contentsList

import android.content.Intent
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import android.widget.Toast
import androidx.recyclerview.widget.GridLayoutManager
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import com.bokchi.mysolelife.R
import com.google.firebase.Firebase
import com.google.firebase.database.database

class ContentListActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {

        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_content_list)

        val database = Firebase.database
        val myRef = database.getReference("message")

        myRef.setValue("Hello, World!")

        val rv : RecyclerView = findViewById(R.id.rv)

        val items = ArrayList<ContentModel>()
        items.add(ContentModel("title1", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FblYPPY%2Fbtq66v0S4wu%2FRmuhpkXUO4FOcrlOmVG4G1%2Fimg.png", "https://philosopher-chan.tistory.com/1235"))
        items.add(ContentModel("title2", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FznKK4%2Fbtq665AUWem%2FRUawPn5Wwb4cQ8BetEwN40%2Fimg.png", "https://philosopher-chan.tistory.com/1236"))
        items.add(ContentModel("title3", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2Fbtig9C%2Fbtq65UGxyWI%2FPRBIGUKJ4rjMkI7KTGrxtK%2Fimg.png","https://philosopher-chan.tistory.com/1237"))
        items.add(ContentModel("title4", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FcOYyBM%2Fbtq67Or43WW%2F17lZ3tKajnNwGPSCLtfnE1%2Fimg.png", "https://philosopher-chan.tistory.com/1238"))
        items.add(ContentModel("title5", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2Fekn5wI%2Fbtq66UlN4bC%2F8NEzlyot7HT4PcjbdYAINk%2Fimg.png", "https://philosopher-chan.tistory.com/1239"))
        items.add(ContentModel("title6", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2F123LP%2Fbtq65qy4hAd%2F6dgpC13wgrdsnHigepoVT1%2Fimg.png", "https://philosopher-chan.tistory.com/1240"))
        items.add(ContentModel("title7", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2Fl2KC3%2Fbtq64lkUJIN%2FeSwUPyQOddzcj6OAkPKZuk%2Fimg.png", "https://philosopher-chan.tistory.com/1241"))
        items.add(ContentModel("title8", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FmBh5u%2Fbtq651yYxop%2FX3idRXeJ0VQEoT1d6Hln30%2Fimg.png", "https://philosopher-chan.tistory.com/1242"))
        items.add(ContentModel("title9", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FlOnja%2Fbtq69Tmp7X4%2FoUvdIEteFbq4Z0ZtgCd4p0%2Fimg.png", "https://philosopher-chan.tistory.com/1243"))
        items.add(ContentModel("title10", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FNNrYR%2Fbtq64wsW5VN%2FqIaAsfmFtcvh4Bketug9m0%2Fimg.png", "https://philosopher-chan.tistory.com/1244"))
        items.add(ContentModel("title11", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FK917N%2Fbtq64SP5gxj%2FNzsfNAykamW7qv1hdusp1K%2Fimg.png", "https://philosopher-chan.tistory.com/1245"))
        items.add(ContentModel("title12", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FeEO4sy%2Fbtq69SgK8L3%2FttCUxYHx9aPNebNwkPcI21%2Fimg.png", "https://philosopher-chan.tistory.com/1246"))
        items.add(ContentModel("title13", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FbdIKDG%2Fbtq64M96JFa%2FKcJiYgKuwKuP3fIyviXm90%2Fimg.png", "https://philosopher-chan.tistory.com/1247"))
        items.add(ContentModel("title14", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FFtY3t%2Fbtq65q6P4Zr%2FWe64GM8KzHAlGE3xQ2nDjk%2Fimg.png", "https://philosopher-chan.tistory.com/1249"))
        items.add(ContentModel("title15", "https://img1.daumcdn.net/thumb/R1280x0/?scode=mtistory2&fname=https%3A%2F%2Fblog.kakaocdn.net%2Fdn%2FOtaMq%2Fbtq67OMpk4W%2FH1cd0mda3n2wNWgVL9Dqy0%2Fimg.png", "https://philosopher-chan.tistory.com/1250"))


        val rvAdapter = ContentRVAdapter(baseContext, items)
        rv.adapter = rvAdapter

        rv.layoutManager = GridLayoutManager(this, 2)

        rvAdapter.itemClick = object : ContentRVAdapter.ItemClick {
            override fun onClick(view: View, position: Int) {
                Toast.makeText(baseContext, items[position].title, Toast.LENGTH_LONG).show()

                val intent = Intent(this@ContentListActivity, ContentShowActivity::class.java)
                intent.putExtra("url", items[position].webUrl)
                startActivity(intent)
            }

        }
    }
}

메세지 나야되는거 적었습니다...그런데도 안떠요