1. Make sure you turn the camera up.
2. Make sure you use a NANO SIM card.
3. The NANO card may not be properly installed, resulting in the short circuit of the capacitor and a failure to recognize that the rear camera is up. Take out and re-insert the card. Be sure to put the card inside the card cover before installing it in the watch.
2. Make sure you use a NANO SIM card.
3. The NANO card may not be properly installed, resulting in the short circuit of the capacitor and a failure to recognize that the rear camera is up. Take out and re-insert the card. Be sure to put the card inside the card cover before installing it in the watch.