My New iPhone 15 Plus Keeps Shutting Down and Won’t Turn On

I bought a 256GB iPhone 15 Plus in December 2024, but soon after, it started shutting down on its own. At first, it would turn back on by itself, but later it completely shut off and wouldn’t turn back on unless plugged in. Over time, the problem worsened—now it shuts down even when the battery is over 70%, and sometimes won’t turn on even when charging. I have to plug and unplug it for hours to get it to power on. The issue comes and goes, making the phone unreliable. I contacted Apple support and followed their instructions, but the problem remains. They suggested sending it to service, but I don’t want to be without a phone or accept an uncertain repair time. I want Apple to address this immediately and refund my money.