With root Android 5.1 kingroot apk, just follow the steps below.
Step 1: Download Root Application Here ➡ Kingroot 5.1.2.apk
Step 2: Installation and open kingroot application.
Step 3: Turn off your data connection, as it is required if your kingroot android phone page.
Step 4: Click on the button "to make way" kingroot will begin the removal process of your device.
Step 5: Then wait for your device to have the message rooted successfully.
So your note Android phone page is all about how you can cancel your phone imposed by the manufacturer's warranty period, but you can still use your device kingroot.