If you have actually obstructed someone accidentally or altered your mind about the block, though, it is likewise reversible. You can alter your Personal privacy settings to unclog and enable somebody back into your Facebook world.
How To Unblock Friends On Facebook
1. Click the down arrow beside "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 beside the name of the person you desire to unblock. A list of the people you have actually blocked is found under the Block Users section.
Suggestion
Uncloging somebody does not instantly put that individual back in your friend list. You need to add the newly unblocked person as a friend and await them to verify the demand.
And one more thing please don’t forget to share this awesome trick to use the How To Unblock Friends On Facebook with your friends.