I have updated my iPhone 6 plus, with the latest iOS11.2.1 and the installation it proceed very well.
The problem is that my iPhone in not working as before anymore.
Batteri niveauet it fall drastically even making all spare settings with background runnig Apps etc..
Before updating to iOS11.2.1 I could make money transaction in supermakert via Bluetooth.
After updating the functionality seems to stop working.
I will appreciate from Apple if it could be made an hot-fix from in order to solve problems caused from Release iOS11.2.1
Enjoy the day
iPhone 6 Plus, iOS 11.2.1