What should you do if such a thing happens to you?

How long has your mobile phone been used now? If it is still under warranty, you can call the Consumers Association directly. Even if your mobile phone has been used for a long time, you can identify it yourself. Why do you have to let them identify you? Nowadays, businesses try to avoid this kind of thing. How can you say that your mobile phone is the manufacturer? If you don't want to make a mountain out of a molehill, buy a new one even if you are unlucky; If you want to argue with them, be tough, after all, it's your side!