No MediaStream in connected peers

[SashaShtal]

I am using simple-peer and simple-signal to connect two clients with webcams.
After creating peer connection and passing MediaStream to it, there is no video on the receiving side, just transparent/black square.

Server side:
`const signalServer = require('simple-signal-server')(io)
const allIDs = new Set()

signalServer.on('discover', (request) => {
const clientID = request.socket.id
allIDs.add(clientID)
request.discover(Array.from(allIDs))
})

signalServer.on('disconnect', (socket) => {
const clientID = socket.id
allIDs.delete(clientID)
})

signalServer.on('request', (request) => {
request.forward()
})`

Client side (Vue.js)
`var SimpleSignalClient = require("simple-signal-client");
var signalClient = new SimpleSignalClient(this.$socket.client); // Uses an existing socket.io-client instance

    function promptUserForID(ids) {
      console.log(ids);
      return ids[0];
    }

    signalClient.on("discover", async (allIDs) => {
      const id = await promptUserForID(allIDs); // Have the user choose an ID to connect to
      const { peer, metadata } = await signalClient.connect(id); // connect to target client , { asd: 123 }, { stream: stream }
      console.log(metadata);
      console.log("initiator", peer); // this is a fully-signaled simple-peer object (initiator side)
      peer.addStream(stream);
      peer.on("stream", (s) => {
        var video = document.getElementById("remote1");
        console.log(video);
        if ("srcObject" in video) {
          console.log(1);
          video.srcObject = s;
        } else {
          console.log(1);
          video.src = window.URL.createObjectURL(s); // for older browsers
        }
      });
      peer.on("error", (err) => {
        console.log(err);
      });
    });
    //console.log(stream);

    signalClient.on("request", async (request) => {
      const { peer, metadata } = await request.accept(); // Accept the incoming request
      console.log(metadata);
      peer.addStream(stream);
      console.log("answer", peer); // this is a fully-signaled simple-peer object (non-initiator side)
      peer.on("stream", (s) => {
        console.log("stream");
        console.log(s);
        var video = document.getElementById("remote1");
        console.log(video);
        if ("srcObject" in video) {
          console.log(1);
          video.srcObject = s;
        } else {
          console.log(1);
          video.src = window.URL.createObjectURL(s); // for older browsers
        }
      });
      peer.on("error", (err) => {
        console.log(err);
      });
    });

    signalClient.discover();`