i think that the sim card of the phone has been discarded by the thief.what do i do? [duplicate]

i think that the sim card of the phone has been discarded by the thief.what do i do? [duplicate] References This question already has an answer here: Find a stolen Android device without sim card 4 answers i have lost my mobile and when i am trying to call it it says that the phone is switched off. i think that the sim card of the phone has been discarded by the thief. what do i do?