hi GM. I'm Greg, 10 years awarded Windows MVP, specializing in Installation, Performance, Troubleshooting and Activation, here to help you.
Are there drivers missing or in error in Device Manager? Have you tried opening them to Update Driver > Automatically?
Have you tried another USB-C port, usually one on the opposite side uses a different controller.
More steps to try here:
https://windowsreport.com/usb-to-hdmi-adapter-n... (Avoid ad links which intrude into editorial copy, especially avoid Restoro and Reimage ads. You also do not need the driver app)
You can trace the Hardware ID of missing drives to find the exact make and model of the device to search as shown here:
http://answers.microsoft.com/en-us/windows/wiki...
If nothing else finds the driver install DriverMax for it's two free drivers a day, to see what driver it finds for this. It's the most reliable driver finder which searches by the hardware ID in it's huge driver database. Set a System Restore point first. You don't' need to buy it, uninstall it when you're done: https://www.drivermax.com/
Feel free to ask back any questions. Please report back results for all steps given so I know what else to suggest if necessary.
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