There's a driver in the device you connected to that isn't supported in the version of Windows 10 Mobile your phone is running. For information about the supported devices, see Universal Serial Bus (USB). Make sure your PC (or phone), the external display, and the cable all support DisplayPort or MHL alternate modes.

DisplayPort over USB-C | Dell UK DisplayPort over USB-C | Dell UK

Yes. Just like in standard DisplayPort connectors and cables, DisplayPort over USB-C can take advantage of the four high-speed data lanes in the USB-C connector and cable to provide 4K display resolutions and beyond on supported products. Your PC might not provide enough power to the USB device. Please connect your device to external power, or try using a different PC.

DisplayPort over USB-C offers a handful of convenient and valuable features that make it a great choice, especially for laptop users. But is it worth upgrading to? Which option you should choose ultimately depends on what you're hoping to achieve, and which technologies are available to you. At the time of writing, HDMI 2.1 is already on the market. It provides the greatest throughput in terms of maximum resolution, frame rate, and color depth, and is a solid choice. The device or dongle you connected to has new features for USB-C that your PC (or phone) doesn’t support.

USB-C to Display Port not working? - Microsoft Community USB-C to Display Port not working? - Microsoft Community

Anyone successful with using a USB-C to DP bidirectional cable to the G-story 15" Portable Type-C monitor? If you have a USB-C analog audio adapter connected to your PC, unplug it, then connect a USB-C digital audio adapter instead. A PC (or phone) with USB Type-C connectors has larger power limits. If the connector supports USB Power Delivery, it can charge even faster at greater power levels. Make sure your PC, the external display, and the cable all support DisplayPort or MHL alternate modes. There's some contention over whether daisy-chaining multiple 4K monitors is possible over USB-C, though. If that's important to you, you're better off going with DisplayPort or opting for a Thunderbolt 3 monitor, instead.To charge faster, your PC, charger, and cable must all support the industry standards. Your charger and cable must also support the power levels your PC requires for the faster charging. For example, if your PC requires 12V and 3A for the fastest charging, a 5V, 3A charger won’t give you the fastest charging. Learn about DisplayPort over USB Type-C, also called USB-C and it's advantages. Find information about how to identify if the USB Type-C port on your PC supports DisplayPort