I have a 2nd Gen iPad 12.9 which was purchased in July 2017. I hardly ever connect this to my iMac but just use the lightning cable to keep the iPad charged. Recently when I have tried to connect it to my iPad it will connect and then disconnect constantly. I have found that keeping pressure on the cable plug where it connects to the iPad stops this happening. I assume there is a weakness in the lightning cable and the contacts are maybe a bit corroded. I don't have apple care on this iPad. Would I be expected to buy a new Lightning Cable or do you think this should be swapped over by Apple?