This does not happen to others.The loss or theft of a smartphone is always very problematic considering the price of these small devices and also the issue of personal data.
In this video, F-Secure tells you everything you need to know to limit the damage.
What to do after but also ... before?
The precautions to take before:
Back up your data.
Lock your smartphone.
Verify that geotagging is turned on.
Install security software.
Note the IMEI number of your phone.
The procedure after:
Try to locate it.
Contact your service provider.
Complaint to the police.
Be reimbursed ... if possible.