If the new product is broken, you should call the store to see how to deal with it. Generally, a good after-sales store will replace it for you, free of charge or charge a maintenance fee of 3-5 yuan/gram.
Even if the old ones are exchanged for new ones, a depreciation charge of 25-50 yuan/gram will be charged, and one gram will be exchanged for one gram.
The manufacturer's cost price ranges from 20-50 yuan/gram, depending on the brand.
It's best to buy it in a reputable store, which is much better after sale.