4K monitor no longer recognized by macOS as 4K

I have an LG 4K monitor which for several years has worked fine with macOS. It's connected via a USB-C cable. Starting a few months ago it would occasionally select the wrong resolution and be down around the 800x600 range, thinking that's all the monitor could do. I would then pull out the wire and plug it back in again and sometimes it would realize it was a 4K monitor. Eventually this also stopped working, but on the reboot of macOS it would often still realize it was a 4K monitor. Now that doesn't work anymore either.

When I go into display settings I can't select a 4K resolution or anything close to it because all that the settings window displays for available resolutions are these lower resolutions. If I connect a PC I can simply select the resolution I want and it works fine, but on macOS there seems to be no way for me to override the choices being presented to me. I suspect there is some detection problem going on, detecting the available resolutions, and perhaps it's the monitor's fault, but I feel like there's got to be some way to override this resolution even if it's a command in terminal? I'm looking for an OS based override. Please advise.