I had a similar issue with HP 4k displays and docks with M1 MacBooks. The was a MacOS update at some point that broke how these devices work through USB-C. One

I had a similar issue with HP 4k displays and docks with M1 MacBooks. The was a MacOS update at some point that broke how these devices work through USB-C. One day they worked, the next they didn’t unless you direct connect to the monitor via HDMI. It’s really irritating, as we bought these displays specifically because the previous Dell displays didn’t work well with Macs. I never isolated it because I hadn’t been to that office for 4-5 months during the pandemic. It’s also miserable as the logging for this stuff sucks and nobody really understands how this stuff works. One of my colleagues had success with a thunderbolt dock.