wow this is a strange error. Not sure what to do. If it was me, I would try unplugging everything from power to make sure all settings are reset, then restart. If that does not work, I would try removing the monitor driver and reinstalling the monitor driver. If that doesn't work, I would use DDU in safe mode to remove the amd drivers and monitor drivers, then reinstall amd driver and monitor drivers. If that doesn't work, I have no more ideas, except maybe try the monitor on another computer and/or the gpu in another computer.