Turning tv on results in back screen

Running libreELEC on Beelink U59 PC via usb. If I turn the TV off with the TV remote , then turn back on , I have a black screen and eventually the TV syas no signal. PC is still powered up but seems there is nothing going thru the hdmi ? I have to power off /on the PC to reboot kodi.

Have read through various threads on both here and kodi forum and most of the advice is pointing to , settings-input-peripherals , CEC adaptor.

When open the peripherals page in kodi , it's blank. Tried this also on a mac with default kodi and its the same ?

Are there no CEC options anymore ?

Damn it my bad title should say Black Screen.

I assume this entails SSH to the box using command line never done that . I am used to using file zilla , will have a google and report back thanks for responding.

OK I ran that and the PC rebooted but hasn't fixed it unfortunately. I checked in putty to see if the process had completed by trying to run it again , got message system has been modified , please run delete if you wish to modify again, so it must have completed. Thanks for your input , I think for my streaming with kodi and LibreELEC , the solution will be to sell the PC and buy one of those s905x4 boxes , a lot less hassle . The reason i went for a PC was the better ram , but I have since found that the processor on this box doesn't support HDR so android box will be better I think. cheers again.