HP laptop won't send signal to external monitor

I have an HP Z Book Firefly and recently it stopped recognizing my external monitor. It's a portable monitor that gets its power and signal from a USB-C to USB-C connection. The monitor and cord has been tested on another computer, it works fine.

No troubleshooting has resolved this. All drivers have been updated, it's the latest Windows software. I have started and restarted the laptop, I have tried different ports. Anyone else encountered this and has advice? There's some setting preventing it from sending a signal.