This happened twice to me this week. I parked the van and paid for my spot. I decided to add more money from another parking meter. You punch in that you want to add money to your spot. After punching in my parking # it said receipt not found. I tried it several times and I did have the right parking space because I had the old ticket in my hand. That really honked me off because twice in 2 different days I had to walk back to the van and move to another spot so I could pay more money so they would not come a put a boot on the van. If this is the case, I think people will shy away from parking down town. I know for me, it was not a great way to start my day.