iPhone 6s boot loop

Hi, is it just stuck on the Apple logo & keeps restarting? Try the following:

Force restart the phone, press and hold both the Home and the Top (or Side) buttons until you see the Apple logo.

If nothing happens, connect your phone to a computer, press and hold both the Home and the Top (or Side) buttons until you see the recovery mode screen (computer with cable).

When asked to update or restore in iTunes, choose Update first & follow the prompts on the screen. Otherwise, choose Restore to install a fresh copy of the iOS software.

If you can't update or restore the phone, bring your phone to the nearest Apple Store or Apple Authorized Service Provider to

get it checked. Book an appointment on getsupport.apple.com or use the Apple Support app. If there are no available appointments, it would be best to call the store directly to book an appointment.

Go here - Force reboot device - Apple Support

go here - Contact Support

This is the next step - If you can't update or restore your iPhone, iPad, or iPod touch