Scrolls don't stack

Hey,

I bought Cinfras Teleport scrolls from the scroll merchant Cinfras. When I tried to list them on the market, it said, "That item can not be traded on the trade market." I noticed, however, that other people were selling them. I decided to buy one of the scrolls. When I did so, I noticed I could not stack the scroll I bought from the trade market with the scroll I bought from the scroll merchant. I cannot list the scroll I bought from the merchant on the trade market.

Why is this happening?

 

It is a game problem. When you obtain the same item from different sources, they do not stack. It is the same reason why emerald block gained from quests may not stack with emerald blocks earned from chests or loot, and why the Az runes earned upon completion of the Realm of Light 1 quest does not stack with Az runes earned from guardians