Users of Apple devices running iOS and macOS 13.4 10.15.4 faced an unexpected problem. They do not have the ability to make audio or video call through FaceTime on smartphones and tablets Apple, which runs iOS or iOS 9.3.5 9.3.6.
It is worth noting that at the moment the solution of this problem. When contacting technical support, staff recommends simply update firmware by installing a more recent version of iOS. However, in some cases, this advice is not working. For example, on the iPhone 4S or iPod touch fifth generation you can’t install a newer version of the firmware.
It is noteworthy that devices running iOS or macOS 13.3.1 10.15.3, are deprived of such problems. With them, users can freely make calls via FaceTime on gadgets with older versions of iOS.
It is assumed that the problem arose because of some bug in new firmware. We can assume that in the near future, the cupertinos will release an update that will resolve the problem.