If you no longer want to interact with or message a user, or you don't want them to be able to interact with or message you, you can block the user. You do not have to be connected with a user to block them.
You can unblock a user by viewing their profile page or by viewing blocked accounts in your user settings.
Note: A user will not receive a notification when you block or unblock them.
Open User Profile
Open the profile of the user you want to block.
Click the Options icon  and click the Block [name] link .
Confirm Block User
Confirm you want to block the user by clicking the Yes, Block link.
View Blocked Profile
After you have successfully blocked the user, you will see a confirmation message with the date you blocked the user . You will also view this message if you later return to view the user's profile.
To unblock the user, click the Unblock Profile button .
Confirm you want to unblock the user by clicking the Yes, Unblock button. After you unblock the user you will be able to view their profile and interact as normal.