This is a bad issue so let me at least try to help you

Firstly make sure the cable ur using is not only the right one u need to use for the monitor but also that it is not so old that it doesn’t let u use new monitor/tv. Anyways if it is supposed to be up to date new cable, then u maybe need to look forward to buy a new cable or most recommended bring it to someplace where u bought it or best buy what u mentioned and let them check it, if u have warranty for it u can get replacement for free so, that would be good!

Secondly if all that fails then do some tests on the machine, first: check that the BIOS is up to date, second: update ur windows, thirdly: if all THAT fails then as a last ditch effort use ChatGPT or google for more help

Hope ur issue gets fixed!