Summoned Heads stay if taken off of stand?

[PlayingWithPi]

Some Quick Info: PaperMC v1.16.5 - Paper build 777 AST - 3.7.2

###Issue So doing /ast enables the plugin, using the nether star opens up the GUI Adding the user's name, gets you the user's head.

However, if you place the player head into your inventory, or drop it outside of the inventory, it doesn't despawn when the user does /ast to stop using the GUI tools.

I would like to see something like one of the options below: NBT stating where the item came from (cannot be changed) Lore stating where the item came from (cannot be changed) Item disappearing if taken away from armour stand so people cannot abuse this to get all heads in-game.