When I start to install software so error come that your internet connection not connected that why failed
Software downloaded but not installing in phone when ever started installing so error occurred you are not connected with internet.
iPhone 7
Try to do a restart. Press and hold the power button for about 5 seconds, (until the menu comes up) and then press slide to power off. Wait 30 seconds, then hold the power button for about 3 seconds to turn it on, then see if it works.