iMac will not charge iPhones any more
Hi
My iPhone 7 and my wife's iPhone 6 charge without problem using wall charges plugged into the mains power
But when plugged into the USB socket of our iMac 21 the phones will not charge and just beep indicating they are not charging
I am not 100% sure but I think this was not a problem before we updated to IOS11
Does anyone know how to fix this please?
iMac (Retina 4K, 21.5-inch, Late 2015), macOS Sierra (10.12.2)