Every time I get the dual displays working, a Windows update or something comes along, and the second monitor is no longer detected. Last time, I had to completely uninstall all drivers and install the latest AMD package. I still had to click on a bunch of stuff before it detected both again. I have no idea what I did to get it back. Today, the second monitor dropped again. Someone please tell me what to do!
Please provide more information about your full system so we can help.
Windows 10 does have a habit of forcing drivers onto your system. With all AMD drivers un-installed on your system, if you download and run the MS Hide Updates package, it should allow you to high the Windows Update AMD drivers that get installed over your current AMD drivers and break your configuration.