Can't get both displays working on my UD-3900Z

Hi, I have a Mac M1. here are the specs:
Mac mini (M1, 2020)
Chip Apple M1
Memory 8GB

I recently bought the UD-3900Z as I need to expand to 4 screens. I am already using the 2 natively supported screens, and want to use the display link HDMI inputs from the UD-3900Z to expand to 4 HDMI inputs. I have installed the DisplayLink drivers. I am plugging all in with regular HDMI to HDMI cables. I have successfully plugged one of the screens into the UD-3900Z and have signal 100% working. However, when I try plug in the 2nd HDMI, there is nothing displayed. There is a display that show in the Display section in System Preferences and it is labelled “No Monitor Display”. So the Mac is technically picking up the screen but for some reason doesn’t want to display to the monitor. I have tested to see if it’s the HDMI ports by having only one screen plugged in with both ports and they’re both working, just not simultaneously. both HDMI cables are working and both screens have displayed, again, just not simultaneously.

Any help would be much appreciated

Hi Anthony,

Thank you for contacting Plugable support. We would like to take a closer look at your system to better help assist but require some additional information. Instead of posting that information here, could you please contact us directly via email? To do this, please email us at In the subject of your direct email, please reference case 363632 which will allow us to match things up and then provide the next steps.

Apologies for the extra steps in the process, and we thank you for giving us the chance to help!

Best regards,

Michael S.

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