If you encounter a problem like yours, you should first negotiate with the seller or manufacturer to solve it. If it cannot be solved satisfactorily, you should go to the Consumers Association for product quality inspection. If it is really a product quality problem, it should pass Legal means are used to protect the rights and interests of consumers. The receipt is evidence of your transaction with the merchant. Now that there is no evidence, the industrial and commercial industry will definitely not care about it, and you will have to admit that you are out of luck