Hello My new Galaxy S8 has some problems revolving around charging the device. Whenever I plug the device in to charge, it doesn't recognise it and doesn't charge. The only exception to this is when I plug the charger in whilst it's turned on and hold down the power and volume down buttons until it powers off, which it then acknowledges it's being charged and charges normally. The second problem is that whenever the phone has the cable plugged into it, it can't be turned on. Is this normal behaviour or is there something wrong with the phone? Thanks in advance.