text: Title: posts_count bigger than 19 results in only 19 scraped posts
  Body: Hi,
  
  When I want to scrape the last 100 posts on a Facebook page:
  ```
  facebook_ai = Facebook_scraper("facebookai",100,"chrome")
  json_data = facebook_ai.scrap_to_json()
  print(json_data)
  ```
  Only 19 posts are scraped. I tried with other pages too, the same result.
  
  Any ideas what goes wrong?