Peculiar issue with USB C DisplayPort monitor and MBP

I have just entered the MacOS world thanks to my workplace gifting me an M3 Max MBP 14" So I have a cheap portable monitor that takes USB C DisplayPort I tried it with my machine, and it worked perfect. Powers the monitor and extends the screen to it as expected, using 1 ThunderBolt cable. I saw that In control centre the Screen Mirroring was enabled and I selected it, I chose an option that I dont remember but it was like duplicate display, and the monitor duplicated my display instead. This was _not_ in the Display>System Settings menu I unplugged the cable and a basic-looking message came up on the screen that said the display couldn't be found (roughly). It was not from the monitor Now when I plug the monitor in it isn't found in Display settings at all, not detected as a monitor, but: Monitor is powered Monitor detects an output from the Type C, auto-selects it and displays resolution info The really odd thing is that I can choose the monitor as an output for my audio. It shows the name of the monitor and the speakers work. So there is some link still between the 2. But I'm not too sure what I changed in Screen Mirroring, I thought that was for Airplay, and sending your display wirelessly or between apple devices Pics show the monitor Info, Screen Mirroring in control centre and the display not being detected