With iOS 13 and later, both of your phone numbers can make and receive voice and FaceTime calls and send and receive messages using iMessage, SMS, and MMS. Your iPhone can use one cellular data network at a time. … This uses Dual SIM Dual Standby (DSDS) technology, which means that both SIMs can make and receive calls.
When you call a dead phone does it ring?
Answer: A: With a dead battery it should not ring but it should go to voicemail directly.