I contact the store explained the situation in writing and they told me that my proof of purchase is required, becase they just need to make sure that I puchase the mattress from them
Unless you paid cash, you have a canceled check or a credit card statement which will prove purchase.
Scott is right - you need a receipt or charge card receipt or something to prove you bought it from them and the date, etc. If you don't have that, or a witness who was there at the sale, then you can't prove that they are the seller who sold you the defective goods. To get them to do anything for you, proof is needed. Good luck.
This answer is for general purposes only and does not establish an attorney-client relationship. The law in your state may differ and your best answer will always come from a local attorney that you meet with privately. If you need a Consumer Law attorney, click the link above to find a Consumer Law attorney near you.
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