I found a Food Lion glitch

I'm not sure if this is happening at every store but it happened to me.

I took these coupons from the Food Lion website when I went shopping on Sunday. The coupons include $1 off FL brand cereal, $1 off Home360 purchase, $1 off Healthy Accents purchase, and $2 off Food Lion green tea 12 pack.

I already tossed my receipt, so I can't give you exact figures but I purchased the following:

Home360 flushable wipes (42 count) = $1.99 roughly** (-$1 coupon = $0.99)
FL Magic Stars cereal = $2.74 sale price (-$1 coupon = $1.74)
Healthy Accents liquid soap = $1.19 roughly (-$1 coupon = $0.19)
plus other things we needed like Gatorade and lunch meat.

**I bought these wipes to go in my diaper bag. First I looked in the baby aisle. The Home360 baby wipes was also a 42 count and they were priced right around $2.30. The Home360 flushable wipes are the same thing except the package doesn't say "baby" on it and it was $0.30-$0.40 cheaper.

At checkout I handed the cashier the sheet of coupons and told her that I did not use the Green Tea coupon. She scanned all 4 coupons (a total of $5 off) and all 4 took. The Green Tea coupon came off of my total even though I did not purchase it. I didn't notice this until I got home and was reviewing my receipt.