MONITOR DOES NOT SUPPORT HDR WHEN PLAYING SOME MOVIES I DOWNLOADED

I HAVE A MAC BOOK PRO - ATTACHED TO A INFOCUS That will not play some movies downloaded to my mac in iTunes, but will play others???

I get the message This monitor does not support HDR

i tried two fixes listed one was change the preferences which initially worked last year when I connected it to another infocus. This year the fix does not work, I was able to stream the movie and play it which ABSOLUTELY MAKES ZERO SENSE, but when the movie is downloaded onto my computer it gives that message.. The fix works still for the two movies I showed (Midway, and 1917) but won't work for robin hood or bravehart. I also tried connecting a USB c to HDMI cord and that did not work either.

There has to be a way to fix it. I am a big time apple MAC book pro supporter but more and more of these glitchy things are making me start to question that. any help would be appreciated.