iPhone 5s GSM - unknown error 2006 on restoring the iPhone, stuck in recovery mode
Solved by pushing it out of Recovery mode cycle by using ReiBoot (https://www.tenorshare.com/products/reiboot.html). I am sure there are some other apps that can do this too. It's very simple to do, I just installed it, run it, plug the iPhone in computer via USB. It detects the iPhone, offers a "push out of recovery mode" button of sort. Click the button and voila!