Latest questions about "blocking"

So every time I blocked and unblocked someone, about a month later I received a notification saying they added you as a friend! Is that an automatic thing or did they really add me again?

If I block someone on Snapchat will I still see their stories on my friends list feed? How can I ensure that they don't have a way to contact me and that I don't have to see their stories on my feed?

How do you know if you have been blocked from someone on Snapchat? I can see the person's name and scores, but the top friends does not show up.

If I send a picture on Snapchat to the wrong person and then block them, they can't see it? But if I then unblock the person, can they then see the picture I send from before I blocked them?

How do you block someone on Viber?

Can I prevent users from entering the blocked sites using Hotspot Shield with the help of Kaspersky Admin Kit 10.0 ?? They are actually using software like Hotspot Shield to bypass the proxy.