Question: what do you do when you lose your iphone?
Answer: Sign in to iCloud.com/find on the web or use the Find My app on another Apple device.
Find your device. ... 
Mark As Lost. ... 
Report your lost or stolen device to local law enforcement. ... 
If your missing device is covered by AppleCare+ with Theft and Loss, you can file a claim for your lost or stolen iPhone. ... 
Erase your device.