Use Find My Device on Android: https://www.google.com/android/find
Use Find My iPhone on iPhone: https://www.icloud.com/find
Sign in with the same Google or Apple account linked to the phone
Check the phone’s last known location on the map
Play a sound to help locate the phone nearby
Mark the phone as lost or enable Lost Mode
Lock the phone remotely with a new passcode
Display a contact number or message on the lock screen
Check location history if it was enabled before the phone was lost
Contact your mobile carrier to suspend the SIM and block service
Report the phone’s IMEI to your carrier
Change passwords for email, banking, and other important accounts
Check for device tracking through Samsung Find My Mobile if you use a Samsung phone
Check for tracking through other manufacturer services if available
File a police report if the phone was stolen
Contact your insurance provider if the phone is covered
Do not share the phone’s live location publicly
Keep tracking the device periodically if it stays online
Erase the phone remotely if recovery is unlikely