HP ENVY 27 AIO - HP Display Controls no longer work

[LodisKnight]

The HP Display Control button and application used to work where I could change the screen brightness, use preset HP color schemes, change to the HDMI Input, etc. But now HP Display Control has all of the options grayed out with a message on the screen that says "Only supported when adjusting the internal display." There is also no display in the "Adjust This Display" dropdown, which I assume is the reason for the message.

This is an all-in-one and has only one display. No external monitors or devices are connected. I have a device plugged into the "HDMI In" and using the manual button on the back works to switch to the HDMI Input properly, it just doesn't due it within Windows. I have already contacted HP Support (L1) and they were not able to diagnose. I have reinstalled all Intel and NVIDIA drivers, as well as the HP Display Control application to no avail. I have five children and utilize Magic Desktop and do not want to have to reinstall Windows. Please assist.

[Echo_Lake]

@LodisKnight
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