Collecting Like, Share, comments from facebook using facebook api

I am trying to scrape a public facebook page using facebook api, but every time i sent request it return

HTTP Error 400: Bad Request

I am putting correct access token, which is app id + “|” + app_secret. But still return Bad request. For safety reason I hide my app id and app secret code.

import facebook
import urllib3
import requests
from urllib.request import urlopen, Request
import json
import datetime
import csv
import time

app_id = 'facebook_app_id'
app_secret = 'facebook_app_secret' 

access_token = app_id + "|" + app_secret

fb_page = "manchesterunited"



base = "https://graph.facebook.com/v3.2"
node = "/" + fb_page
parameters = "/? 

fields=message,link,created_time,type,name,id,likes.limit(1).summary(true),comments.limit(1).summary(true),shares&limit=%s&access_token=%s" % (100, access_token)
 url = base + node + parameters

def request_until_succeed(url):
    req = Request(url)
    success = False
    while success is False:
        try:
            response = urlopen(req)
            if response.getcode() == 200:
                success = True
        except Exception as e:
            print(e)
            time.sleep(5)

            print("Error for URL %s: %s" % (url, datetime.datetime.now()))

   return response.read()
 test_status = json.loads(request_until_succeed(url))["data"][0]
 print (json.dumps(test_status, indent=4, sort_keys=True))