If you have actually obstructed someone unintentionally or altered your mind about the block, however, it is likewise reversible. You can alter your Privacy settings to unclog and permit somebody back into your Facebook world.
How To Unblock Facebook Friend Request Block
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 "Unblock" link next to the name of the individual you wish to unclog. A list of individuals you have actually blocked is discovered under the Block Users section.
Suggestion
Unblocking someone does not instantly put that individual back in your good friend list. You must include the recently unblocked person as a friend and wait on them to validate the request.
And one more thing please don’t forget to share this awesome trick to use the How To Unblock Facebook Friend Request Block with your friends.