DIAGNOSIS The monitor is receiving power (hence the light) but not a video signal from your source device. This usually means the USB-C cable you're using is power-only, or your device isn't set to output video over that port.
FIX First, swap the USB-C cable. You need one that explicitly supports "video" or "DisplayPort Alt Mode," not just charging. If that doesn't work, check your source device's display settings. On a Windows laptop, press Windows Key + P and select "Duplicate" or "Extend." On a Mac, go to System Settings > Displays. Also, try the other USB-C port if your laptop has two.
IF THAT DIDN'T WORK Try connecting via the included mini-HDMI to HDMI cable instead, using a separate USB-C cable just for power to the monitor's other port. This isolates if the issue is the USB-C video pathway.
HEADS UP Some phones and older tablets require a specific adapter or a direct USB-C video-out setting to be enabled in developer options. The InnoView won't force the signal if your source device isn't sending it.