The back cover is cracked

iPhone 14 pro max. I've been using the phone for 7 months. During the entire time of use, the phone did not fall.

In the evening, I put my phone on wireless charging. I charged the phone to 90% and took it off the charge, then I talked on the phone. There was nothing wrong with the phone. At night, I put the phone in the bedside table without charging. In the morning, when I picked up the phone, I saw the stripes on the back cover. When I took off the cover, I realized that these were cracks. The battery on the phone is swollen and the phone is deformed. When it lies face down on the table, the backlash is 1 mm.