iphone 17 battery

I'm having battery problems with my new basic iPhone 17, today I left it completely turned off for 7 hours and it consumed 7%, I don't think it's normal given that when completely turned off the battery shouldn't drop in theory, or at least very little. I've had the phone for two days, I would like to know if it's a software issue or if it's my phone that's faulty, if so I would change it. Has anyone had the same experience as me with this phone? to also find out if it is the iPhone 17 that does this.