How to Block Someone Who Has Already Blocked You on Facebook
This article will outline the steps you need to follow in order to block someone who has already blocked you on facebook
1. Click the padlock icon in the blue bar at the top your Facebook page. This is a shortcut icon to your important privacy settings.
2. Choose “How do I stop someone from bothering me” to open the blocking form.
3. Enter the email address of the user you would like to block and click “Block.” Although the directions say you can also enter a name, since this person has already blocked you, that method will not work.
You can see a list of blocked users, and unblock them if you wish, by clicking the gear icon, choosing “Privacy Settings” and selecting “Blocking” in the left column.