If your QR code scans fine when it's on the screen, but not when it was printed we probably just need to make it a bit bigger. We will do this reprint for free. We make a lot of chips with QR codes so the operators actually scan the chips to make sure they work before we ship them.
Some phones scan really small QR codes fine, but if you want to be safe, your QR code should be at least .8 inches x .8 inches. The printable area on the Composite Poker Chips is 1.3 inches and about 1.1 inches for the Clay Poker Chips so the QR code should take up the majority of the chip's designable area.