New iPhone 16 Pro freezing and not turning on

Contact Apple support.

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Alh10 wrote:

My iphone 16 pro (brand new) doesn't always react. Sometimes it freezes and I cant turn it off. Or sometimes I can't turn it on even if it fully charged. Seems unreliable.

just two more points

Re not being able to turn it on or off, you can always try https://support.apple.com/guide/iphone/force-restart-iphone-iph8903c3ee6/ios

Re not being able to turn it on, I hope you do not regularly turn it off. There is generally no need.

But yes get Apple to look at it.

Was this iPhone purchased from Apple or an Apple Authorized seller, or some 3rd party (such as Amazon)? If you go to Settings/General/About is the warranty coverage all the way to a date a year from the day you bought it?

Do you have the latest version of iOS 26.0.1 on it?