Problem with rogues chests and stackable clues?

Basically the chest is only supposed to give you the 2 dose pray potion loot roll if you can't get hard clues

I had 2 clues in the bank and 2 in my inventory and it gave me a 2 dose pray pot, I have all the capacity increases and can hold 5 hard clues.

I made doubly sure I didn't have an opened hard clue in my bank, it gave me the pray pot even though I can stack 5 clues and only had 4.