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I bout a 330 coca cola can this morning and dialed *120*2653# as instructed and then entered the pin code under the ring of the can. The response that I have received was saying that the pin code I entered has been used already or invalid. What is worrying me further is the fact that this has now happened for three if not four times. My question to the promotions manager is what is wrong with the provided pin codes? Are coca cola employees using the pin codes before sealing the cans and the bottles perhaps? Remember, there is a cost involved when we dial.