Photo-me kiosk cheater

Today I went to take a instant photos at those kiosk in NTU. It costs $6 for 4 photos. I inserted a total of $7 notes and guess what? The machine did not return me $1. Big time cheater! I wonder how many people in NTU has been cheated by Photo-me in NTU canteen B. So next time remember to give exact amount regardless what vending machines. I hope that machine rot!