Use ‘Find My’ to turn on ‘Lost Mode’ or ‘Erase This Device’: Tap ‘Find my’ on iPad or go to www.icloud.com and click on ‘Find My’, select iPhone and select ‘Lost Mode’ or ‘Mark as Lost’, add phone number and message as needed or ‘Erase This Device’ (all content and settings will be erased when iPhone connects to the internet. If Find My network is enabled (in Apple ID ❯ Find My), you will still be able to locate the iPhone)