If you have actually blocked someone accidentally or altered your mind about the block, however, it is also reversible. You can alter your Privacy settings to unblock and enable somebody back into your Facebook world.
Can I Unblock Someone On Facebook
1. Click the down arrow next to "Account" at the top right of any page on Facebook.
2. Click "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 "Unclog" link next to the name of the individual you want to unclog. A list of the individuals you have actually blocked is found under the Block Users section.
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Uncloging somebody does not instantly put that person back in your buddy list. You should add the recently unblocked individual as a friend and await them to confirm the request.
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