Added a new, second UGA-165+monitor and the existing UGA-165+monitor stopped working.

I have used a UGA-165 adapter with my Dell Inspiron laptop for about 8 months. Only one hiccup in that entire time where one day it did not light up. Changing USB ports caused a driver re-installation and it worked again on the new port and since has worked in all ports again. All this time I have also had a third Acer screen connected via the HDMI which always works.
HERE IS MY QUESTION. I just added a second UGA-165 adapter+Acer monitor and it immediately started up and is working flawlessly. But now the first UGA+Dell monitor combination - which has worked for months - now does not work! The Dell monitor powers up, says it detects no signal and goes into standby/sleep mode. The UGA is lit (both of them) and Windows 10 display settings shows that the Dell monitor is detected and as far as Windows knows it is working. The dark Dell monitor is between the laptop and the new UGA+Acer monitor and the desktop is extended across it. I can drag a window from the working laptop display across the dark monitor and after the appropriate amount of dragging it reappears on the next lit UGA+Acer monitor, so the resolution and screen area seems to be accounted for properly by Windows.
I have tried unplugged reboots and fresh installs, uninstalled the adapter and driver with Device Manager and forced rediscovery, just tried the latest drivers too. Windows always finds the UGA and the Dell monitor (even knows the monitor’s make/model) but as I said monitor says “no signal” and sleeps.
My setup is Dell laptop display, Dell monitor+UGA, Acer+UGA and Acer from HDMI port. I began to look at the Control Panel settings and saw the PID seems good but have gone no further.
Is this familiar to anyone?

Hello Brian,

It is hard to say what is really going on without seeing logs. I will follow up with a direct email and instructions.

Thanks for the rapid response!

I just wanted to follow up on the excellent and rapid customer support.
This turned out to be a non issue and I solved the problem myself when I finally really did start from scratch. I had only been uninstalling the non-functioning UGA.
When I uninstalled BOTH UGAs and their drivers using Control Panel and then forced a complete fresh installation both units came up and no longer interfere with each other.
I have been running for about 24/7 now and all is perfect.

Thanks for great support and a great product.

Hi Brian,

Thank you for your kind words!