He's using the wrong spell. He should write a letter containing "Cashus multiplicatum !" Written in 45° with green ink using the feather of a great eagle.
I was thinking the person who had to write this was ticked off because they had to write a custom letter to address the forms sspecifically. On the other hand maybe they get a lot of these and now they have a generic response prepared.
It sucks because when they respond like this, they just give more fire to the flame of these idiots who think that by acknowledging the receipt of ‘coupons’ or other magic spells, that somehow it’s valid but willfully rejected and that they have standing on principle, legally speaking. It’s lose-lose for the people who have to deal with them even though the business will have ample evidence to go after the money in court later. I just hate that regular people have to waste time with this.