After updating your website, if you notice that Facebook is still showing old content or images, you may need to manually clear their cache. After making sure you have published any changes you've made to your website, use the Facebook Sharing Debugger.

Enter your web page URL that needs to be updated into the field labeled "Input URL, Access Token, or Open Graph Action ID" and then click Debug. After clicking Debug, you will be provided with detailed information about your website. It is not necessary to take action on the information provided in order for website information to be updated; clicking Debug will clear the cache.

NOTE: If you need to update several pages with Facebook you will have to debug each page. If you only enter your root domain name, only your homepage will be updated.