Nowadays, smartphones are basically kept in hand. Although they are equipped with protective cases, they are still inevitably subject to some bumps and wear. In severe cases, they will be slightly deformed or even severely deformed. The most reasonable way to deal with such a phone is to replace the back cover.
If the back cover is normally worn, bumped, or slightly deformed, you can try to replace it yourself. Of course, you must have experience in disassembling and assembling the machine before you can try it. It is not recommended to disassemble and assemble the seriously deformed one yourself, because when the motherboard is deformed and stretched to the point where the screws are removed to restore it, it is very likely that the inner layer of the motherboard will break.