The Beaconator

I have this Minecraft world and I used ZERO cheats and I got the beacon achievement but my boyfriend didn't receive the achievement, is it because my boyfriend isn't the owner of the world or?? Please let me know.  I also had trouble getting the achievement myself, I had to break one block from the pyramid and the beacon and log off, then come back and place it back where they belong to receive the achievement.  I don't know if it's a bug or not but thanks for reading!!!