Food/Meal Benefit that the employee can adjust the value of monthly.

I have a use case for a client where the employee receives two benefit cards, one for Food and one for Meals, he can change the amount he receives on each card every month. I tried to find some rate setting that he could enter and the values would be readjusted/calculated automatically, but I couldn't find it.

Now I'm trying to validate with Fast Formula at a rate that the employee will enter the values, but we can't verify where the value that appears on the screen when typing to perform the validation is recorded.

I put prints of how it is configured in the attached document.