Make it a rule with your purchase to take the check. This document is much easier to prove that the goods you have bought in this store. Bought it today, not a month ago.
If a check you do not have to prove that you went to the store and bought the product, can recording from the surveillance camera. Today, many entrepreneurs establish outlets in a security system. Ask to review the record to convince store workers that you were doing your purchase here.
Go to the seller and show a bad acquisition. If you are a regular customer at this store, tell me what you come here for shopping every day, and you extremely uncomfortable. As a rule, regular customers always go forward and return the money or exchange the item even without a receipt. Particularly well this technique works when the "audience". If you store a lot of people that sellers are not willing to earn a bad reputation point, immediately apologize, saying that the misunderstanding happened, which will never happen again, and solve your problem.
If the seller does not want to talk with you and to take back the goods, please contact the shop administration. Threatened that if a defective product you can't exchange, you'll bring it to the station. Checks sanitary control, the store owners are afraid, since they can always find violations in the point of sale.
In the case that a conversation with the store owner will not give results, do take the expired product in the sanitary-epidemiological service. Write a statement that this is the number that the store you purchased certain products, and later found that it was expired. Shall describe in detail when you came into the store, talk to anyone, what results were achieved. Attach to the application a check for the purchase itself and the goods with expired shelf life. The station will be obliged to take action on your letter.
Another instance, in which you can turn to for help – the society for the protection of the rights of consumers. They consider all cases of cheating customers – whether it's food, household items, clothing or something else. In the same way as for the station, to the President of the society write a letter detailing your problem, attach a check, and he goods. After that employees of companies with your letter will go to the point and will deal with your offenders. Explain the sellers rights and obligations of consumers and will be forced to refund you for the product.