Smoke and Fire Bombs

For some reason, Smoke Bombs and Fire Bombs are unable to be accessed after an rb if you bought one. The game still seems to count them there in your inventory, but they are not visible or usable.

I found this out when I was trying to buy firebombs/smokebombs. I was able to buy 2 smoke bombs (before RB I used two), but although the supply NPC took my money, I didn't see the bombs in my inventory, and the NPC claimed I already had the maximum allotment.