iPhone 6 charging but not switching on !
I have an iPhone 6 which works very well, but recently it had switched off due to low battery and is not starting up again. I have been charging it up for past 12 hours from the wall outlet , it registers the cable (shows the image on the left) but does not charge . I tried to hard restart but it didn't work. Finally when i take out the charger it shows the image on the right. I'm stuck up and don't know what to do.I have tried this process again and again!
iPhone 6, iOS 10.3.3