Mystery of the missing lunch money

I thought I was doing good by putting money on Mackenzie's account so she could eat lunch at school when she wanted to. So she wanted to get the toasted cheese sandwich (surprise, surprise) yesterday and she should have 10 bucks on her acct. so I didn't worry about it. She came home with an envelope stating your child needs lunch money. So I went to look online at her acct. Last week it said she ate there on tues, wed, thur and friday. I know for a fact she did NOT eat lunch there on friday because Jed and I took her lunch. So, I looked at the menu and knowing my daughter know she is not about to eat tuna salad sandwich, enchiladas or oven fried chicken. So, the investigation began. I went to the school and told them the problem and the lady in the cafeteria was very nice and said she would investigate this when Ms. Denega's class came for lunch. She and I both think another kid has her number probably by mistake and we need to figure out who. She however can not refund my money and so that will have to be dealt with downtown and she said she will call them. I will probably have to go back up there to keep the pressure on and figure this out but it's just ridiculous!