ASUS MB168B monitor DisplayLink weird problem

I am using an Intel NUC7i5BNH mini computer running Ubuntu 18.04.

I have a portable ASUS MB168B monitor which I am trying to successfully connect to it.

I’ve downloaded and installed the DisplayLink drivers from here https://www.displaylink.com/downloads/ubuntu

However, the only way I can get a proper display on the MB168B monitor is if I also have another HDMI monitor connected to the same computer via the HDMI port at the same time.

I can change the display settings on Ubuntu to just use the one monitor, or both , extended, or mirrored etc. and all looks fine.

But as soon as I plug out the HDMI monitor tho, I see only squiggly lines on the MB168B. So therefore nothing can be displayed properly on the MB168B unless I have another HDMI monitor plugged in at the same time. I can’t understand this.

Would anyone have an idea as to what is the issue here? I’ve tried different drivers etc. Thanks in advance.