how to read Firebase data via Dialogflow

Question

Hello!

I’m having difficulty reading the Firebase data via Dialogflow, I tried several ways, I saw some tutorials, but I did not identify the error, if anyone can help me, I thank.

Firebase rules:

{  "rules": {
".read": "true",  // 2021-2-10
".write": "true",  // 2021-2-10}}

Bank insertion code (working):

function fire(agent){
var newkey = admin.database().ref().child('Pedidos').push().key;
admin.database().ref('Pedidos/'+newkey).set({ 
nome: agent.parameters['nome'],
endereco: agent.parameters['endereco'],
pedido: agent.parameters['pedido'],}); 
agent.add(agent.parameters.nome+' seu pedido foi anotado, aguarde confirmação!');}

function for bank reading(not working):

function lerDados(agent){return admin.database().ref('Pedidos/-MQnoqzRo1rkIxJu8D1g').on("value", function(snapshot) {
var reg = snapshot.getValue();
  agent.add(reg.nome);
 }, function (errorObject) { agent.add("The read failed: " + errorObject.code); });}

Firebase reference data (-Mqnoqzro1rkixju8d1g), in which I want to bring the data:

-Mqnoqzro1rkixju8d1g

address: "Flower street of Jasmin"

name: "Gustavo"

Request: "1 x-all"