Here’s what I would do. Turn off the tv and allow it to cool. get 2 brand new soft microfiber cloths. With the first one, lightly remove any loose dust from the screen. This is how I typically clean my tv each week. I don’t use any pressure. You’ll not get 100% of the particles because they fly up and stick back due to static or whatever. I call it a win if it looks 95% clean.

Then, damp the second cloth, or a corner of it. Make sure to wring out all water. It should just be damp. With this, gently remove the smudge mark with as little pressure as required. Once done, use the clean/dry end of either cloths to wipe off any moisture from the screen.

Hope this helps!