We are several who do not hold the wait and we have managed to install the betas of iOS 13 on our iPhone, being aware that it could have failures, of course. Unfortunately the iOS 2 beta 2 brings an important bug for those who have an iPhone XS or XS Max.
The problem detected is super simple: The iPhone simply does not receive calls when it is in a 4G network, giving the same the operator that is being used, while the person who is calling you is directed to the voice mailbox or encounters the message that the equipment is off or outside the coverage area.
I personally was affected by this problem when I realized that for no reason I received an SMS saying that X person was calling me when my iPhone was not available. Not only were SMS, They also told me the same people who were trying to call me unsuccessfully.
But the strangest thing is that I can make calls with total normality, but I CANNOT receive them if I am in a 4G network, since when receiving a call, the iPhone does not go down from 4G to 3G to receive the call and that is why it is lost, although those with 4G Voice (VoLTE) are saved from this problem.
The error is not only what I am reporting, there are several people who have come to the developer forums Apple to inform what is happening, being several the harmed ones. At the moment the only solution for this problem is have an operator that has the 4G Voice service enabled or configure the iPhone to only connect to 3G networks.
It is the only solution available for those who are presenting this problem that It has only been detected on iPhone XS and XS Max that are with beta 2 of iOS 13 and the modem firmware is 1.51.07, version that you can see in the Information section of the Configuration menu – General.
Now we just have to wait until Apple solve this problem, which is already aware because there have been more than 10 reports that have received, at least this is reported by the Feedback app. We will probably see this bug fixed with the arrival of beta 3 of iOS 13 for developers, which should happen tomorrow or next week.