Click on your account icon in the top right corner and select Settings.
In the settings menu, choose Security and Privacy.
Scroll down to the Blocked Accounts section to see a list of users you’ve blocked.
Find the user you want to unblock.
Click the Unblock button next to their name to remove the block.
Once unblocked, the user will be able to interact with your content, view your profile, send messages, and follow or add you as a friend again.