Hello,
If you are having issues after updating to a higher version of the OS please make sure to check if the docking station/video adapter is detected under the USB bus. For instructions check:
My DisplayLink device does not work at all when connecting on macOS X
If the device is not detected, please powercycle the docking station. So unplug it from the computer and power for 15-30 seconds and re-plug power and the USB cable. Test if it is working.