Kodi Raspberry Pi 4 with Original 7" TouchScreen Display + HDMI output

Hi as subject topic, I still newbie.

I was installing KODi LibreELEC-RPi4.arm-9.2.1 with my 7" touchscreen display, it works fine and also managed to rotate it with SSH from this thread guide.

However i just received my Micro HDMI to HDMI port, when I put in the HDMI to my AV Receiver It didn't show anything.

Is there anything I need to do to turn on this?

Btw what is the different between LibreELEC and OpenElec?

Thank you.

The menu display only showing like this:

Thank you.

no hdmi cable is working fine, if i remove the ribbon cable for 7" touch screen, the display work on hdmi.

if 7" touch screen ribbon cable is connected the display only work with the 7" touch screen.