Iphone 15 pro max freezing

I just bought the iPhone 15 max Pro. Ive had it since late September and two times already the phone has frozen to where I cannot restart nor do anything on the screen but change my background picture I tried to voice command a restart did not work the first time it was frozen for about 20 minutes. The second time I was at work and it was frozen. I could not do anything I had to leave flashlight on and let the phone die to restart it. I tried holding the buttons to reset it that way it did not work is anybody else having this problem?