I have an Anker Power Core 20100 power bank which I have used only a handful of times since I bought it a couple of months ago and have just started to notice that it is making my iphone xr incredibly hot within about 10-15 mins. I have tested the phone with the wall charger that it came with and after 30 mins there is no heat at all. Could it be the cable or the powerbank (or both)? The cable is one that I bought online and so I will test it with the Apple cable to see if that makes a difference. I am concerned about doing damage to my phone.