Assistance Needed with My iPhone 13 Pro Max

I am experiencing an issue with my iPhone 13 Pro Max that started within the last 24 hours. The device powers off every 1–2 minutes, even though the battery is at 84%. I haven’t made any significant changes to the phone recently, other than updating to version 18.1.1.

Could you please assist me in resolving this issue? I would greatly appreciate your guidance on the next steps.

Thank you for your time and support.