If you have blocked somebody unintentionally or changed your mind about the block, however, it is also reversible. You can change your Privacy settings to unclog and permit someone back into your Facebook world.
How To Unblock The Friend In Facebook
1. Click the down arrow beside "Account" on top right of any page on Facebook.
2. Click "Personal Privacy Preferences" from the Account menu.
3. Click the "Edit Your Lists" link under the Block Lists heading. It is at the bottom center of the page.
4. Click the "Unblock" link beside the name of the person you want to unblock. A list of individuals you've obstructed is discovered under the Block Users area.
Suggestion
Uncloging somebody does not immediately put that person back in your friend list. You need to include the recently unblocked individual as a good friend and wait on them to verify the demand.
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