Hard Reset APPLE iPhone 6S - Factory Reset via the Settings menu
Hard Reset APPLE iPhone 6S - How to restore your iphone
Hard Rest APPLE iPhone 6S - restore your phone by using iTunes
APPLE iPhone SE Hard Reset / Bypass Passcode / Restoring / DFU Mode
APPLE iPhone SE Hard Reset / Bypass Passcode / Recovery Mode / Format
Hard Reset will erase all of your data
All described operations you are doing at your own risk.