If you have obstructed someone unintentionally or altered your mind about the block, however, it is likewise reversible. You can change your Privacy settings to unblock and allow someone back into your Facebook world.
When You Unblock Someone On Facebook
1. Click the down arrow next to "Account" on 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 wish to unclog. A list of the individuals you've blocked is discovered under the Block Users section.
Tip
Unblocking someone does not instantly put that individual back in your friend list. You should include the freshly unblocked person as a pal and wait on them to verify the request.
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