Not Bug Organizing inventory with two valentines day nx items makes one disappear from inventory

I have a habit of organizing my inventory every time I get new items, and this is the second time that this bug has happened to me. The first time was with a looking for love nx, and the more recent time was with a pumping heart nx item. I don't need a refund for the nx items, but I would like to see the bug fixed before I haphazardly organize my inventory again with multiple event nx items.

I'm thinking that the bug is probably due to the items stacking when there can only be a single event nx per slot.

 

That NX item stack, but since NX items can't show quantity you can't see the true amount you have without dropping them to unstack it.