Video: Will Apple's new iPhones explode if they wirelessly charge while plugged in? It hadn't occurred to me until I was asked the other day what would happen if you put an iPhone X/iPhone 8 that's charging using a cable down on a wireless charging pad.
The blinking blue behavior is some general "I'm not charging right" signal. The problem may be coils misaligned as the previous poster said, but it can evidently be other things too. In my case it was a cheap USB cable that was the problem .