I have a samsung monitor connected to my 2020 Lenovo P15 laptop running Windows 10 via HDMI, the monitor screen will not wake from sleep (for example, after locking the laptop) unless the HDMI cable is plugged and un-plugged. Even changing the windows display settings (PC only-> extend) will not wake up the monitor.
I have already looked into the display settings on the monitor. previous posts suggested changing the HDMI version settings, but that option does not appear in the samsumg monitor menu. I do have the option to change displayport version, but I don't think that is applicable in this case.