It’s really hard to say for sure, because there’s almost never accessible logs from the monitor or USB controller. First course of action is usually firmware updates. Monitor firmware, PC BIOS/UEFI. Then try swapping hardware. Make sure your USB-C cable is appropriately rated to carry video of the resolution you’re using, plus the USB traffic. I assume it’s not also carrying power. Then try different USB-C ports on the PC (front/back/addon cards).
If possible, you might try changing from USB-C to USB-B connections to see if that’s any more reliable. Or at least use separate cables for video and USB. A quick check of the manual suggests that’s supported.