Websocket closes immediately

https://github.com/tiasimoneriley/pulse

So i am trying to make this code run to get the pulses, however the connection to Websocket is immediatly closed and I don't understand why.

It closing right away is not letting the frames of the video get computed to get the pulses.

Also, I am new to this whole thing so if anyone can figure it out please tell me whats wrong.

Thank you.

This is what my console shows

websocket open!                                    websocket.js:5 
closed                                             websocket.js:22 
T1                                                 camera.js:70
T2                                                 camera.js:76
T3                                                 camera.js:82 
T4                                                 camera.js:84 
T5                                                 camera.js:86 
begin startCapture()                               camera.js:397 
T6                                                 camera.js:88 
WebSocket is already in CLOSING or CLOSED state.   websocket.js:18
WebSocket is already in CLOSING or CLOSED state.   websocket.js:18

Here is the app.py

import json
import os

from flask import Flask, render_template
from flask_sockets import Sockets

import model

app = Flask(__name__)
sockets = Sockets(app)


@app.route("/")
def index():
    return render_template("splash.html")


@app.route("/begin")
def get_heartrate():
    return render_template("index.html")

    
@sockets.route('/echo')
def echo_socket(ws):
    while True:
        message = json.loads(ws.receive())
        signals = model.parse_RGB(message)

        ws.send(signals)



if __name__ == "__main__":
    from gevent import pywsgi
    from geventwebsocket.handler import WebSocketHandler

    port = int(os.environ.get('PORT', 5000))
    print("Hosting on port {}".format(port))
    server = pywsgi.WSGIServer(('', port), app, handler_class=WebSocketHandler)
    server.serve_forever()

and this is the websocket.js

var dataSocket = new WebSocket(location.protocol.replace("http", "ws") + location.host + "/echo");

dataSocket.onopen = function(){
    console.log("websocket open!");
    console.log(dataSocket);
}

dataSocket.onmessage =  function(e){
    var data = JSON.parse(e.data);

    if (data.id === "ICA"){
        camera.cardiac(data.array, data.bufferWindow);
    }

}

function sendData(data){
    dataSocket.send(data);
}

dataSocket.onclose = function(){
    console.log('closed');
}