Thez code seems correct. The only thing I can imagine is your character being younger than 23 y.o. The potion makes you 5 years younger, so in order to avoid your girl being underage, the potion won't show before she reaches 23. Could it the reason?
1 year ago(+1)
Ah, that would be the cause. My character is only 21. I had expected the effect of the Potion of Youth to increase my life expectancy, not lower my age. Which was something I was starting to need since my life expectancy had plummeted to 30.