When the robber connects to Internet then all your data will be erased bro. But too bad you didn't switch on location services if not now could have caught the robber by tracking his location by find my iPhone but still if he switched off your iPhone can't track him. But with imei number just go to police station and make a complaint. They'll block the iPhone itself making it totally useless for anyone. You need to sign in to iCloud and erase the device.
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