To screen mirror your iOS device, ensure that it is connected to the same Wi-Fi channel and frequency (2.4 GHz or 5 GHz) as your Android TV. Once done, simply follow the steps below:
You may need to split the WiFi band into 2.4Ghz and 5Ghz if your device is unable to detect the TV.
Refer to your router manual or contact your Internet Service Provider for more information on WiFi band splitting.
Note: The picture below is for reference as the name of your TV could be different.
Click here for tutorial on using Airscreen
As Airscreen is a 3rd party app, PRISM+ is unable to guarantee its compatiblity and support. Do contact the app developer in Google Play for more details.