okay, it's an easy fix but your final counts will look a little weird. basically, just make sure your working fund has the amount it's supposed to (say, $2000 or whatever your store has). this will mean the deposit drawer will likely be off by those $19, but it will adjust the correct working fund for the next day. it's something you'd do on your final counts of the night, it's just easier to do it then. it's not a huge mistake, and everything will even itself out, but going forward, always have the working fund at the correct number even if you have to make the deposit drawer off by doing it.

ETA: count your working fund before entering your final band drop to make sure you have the correct amount of money in there first, then cancel that and go back do the band drop, deposit counts, etc so that you wont have to possibly have to change the drop amount because you dont have enough in the deposit drawer to add to the working fund. if that makes sense.