Dual Sim 2 Carriers
Does the device have to be unlocked if you are using 2 US carriers?
iPhone 13 Pro Max
Question marked as
If both phone lines are provided by the same carrier that is currently working on your iPhone, then the device can be locked to this carrier.
If both phone lines are provided by different carriers then the iPhone will have to be unlocked so that it can work with multiple carriers.
Axel F.