Named piglins reappears after being killed

1 load into the nether & kill named piglins.

2. I then leave the nether/logout of game.

3. I return to the nether & the piglins have respawned.

4. It happens either by leaving the nether or logging out of the game.

5. We named our piglins with a single fullstop/period.

6. We replicated this multiple times with different players & it still happened. We ended up with 4 double chests of the same loot. 

This happened on my realm

https://imgur.com/a/eyPfSTN this is the link to the clip