* If a missed call comes from an unknown number, try to identify the car number before you call back. Or stop calling back. * Remember that if you are cloning SIM, you will get a missed call. If you receive a direct ring, you will not be a victim of SIM cloning. Be alert when a missed call arrives. * If you see that your cell phone balance is declining unnecessarily, call the call center immediately. * Turn off your cell phone now and call your number from another number. See if it rings. If the ring, you are a victim of SIM cloning. Everyone be careful , stay well.