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I would like to manage my inventory using a barcode system, but I am afraid that people will be able to scan or copy my barcode and make duplicates.
I would like to offer a discount card that has a unique barcode for each customer. It is important that customers cannot rescan or duplicate the barcodes because each barcode is a voucher for 5, 10, 20 taxi rides.
How can I prevent people from duplicating my barcodes and reusing already purchased services?