How do I block or unblock someone?
To block someone:
- Tap their username to go to their profile
- Tap
(iPhone/iPad) or 
(Android) in the top-right - Tap Block
To unblock someone, follow steps 1-2 above and then tap Unblock.
People aren't notified when you block them. Learn more about blocking people.
Note: You can block someone using the Instagram app on your phone or tablet, but not on the web.