테스트 하려고 로컬호스트 창을 띠우니 갑자기 사이트에 연결할수 없음으로 나옵니다.

from flask import Flask, render_template, request, jsonify
app = Flask(__name__)

from pymongo import MongoClient
import certifi

ca = certifi.where();

client = MongoClient('https://downloads.mongodb.com/compass/mongosh-1.5.4-win32-x64.zip', tlsCAFile=ca)
db = client.dbsparta

@app.route('/')
def home():
   return render_template('index.html')

@app.route("/mars", methods=["POST"])
def web_mars_post():
    name_receive = request.form['name_give']
    address_receive = request.form['address_give']
    size_receive = request.form['size_give']
    doc = {
        'name':name_receive,
        'address':address_receive
        'size':size_receive
    }
    db.mars.insert_one(doc)


    return jsonify({'msg': '주문 완료!'})

@app.route("/mars", methods=["GET"])
def web_mars_get():
    return jsonify({'msg': 'GET 연결 완료!'})

if __name__ == '__main__':
   app.run('0.0.0.0', port=5000, debug=True)

왜일까요,,?ㅠ