While playing Bioshock Infinite, I came across a Vigor vending machine with the 2nd possession upgrade in it (lowers cost of using possession). I didn't have enough money, so I simply passed it by assuming I'd see it again.
I've gone a long way (and now have enough money) and none of the subsequent vigor vendors have that specific upgrade. Did I miss it and will never be able to have it now? I read somewhere that the upgrades in the vending machines "stack" and once seen, they'll be available in later ones and that seems true for all of the rest, just not the one I want.
Any insight would be appreciated.
Edit: This is for the XBox 360 version in case this is a bug.