For simulators
The iOS simulator for the specified OS version is not installed on the PC. Change the OS version of the iOS simulator used in the Edit test screen or install the corresponding version of the iOS simulator by the following.
Click Xcode > Settings.
Click Platforms > + > iOS.
Select the desired simulator and click Download & Install.
For real devices
For some reason, the connected iOS real device is not detected by MagicPod.
Follow the procedure here to check whether the real device is detected.