Grammatophyllum question

[johnny31623]

Hello everyone

SORRY for posting at the wrong category
can someone also tell me how to delete the post?
I couldn't find it from EDIT/DELET option, thks

I'm new here
I got a grammatophyllum scriptum hihimannu couple weeks ago and has been sitting at my window sill due to the cold weather in southern Texas.
and finally this week the weather starts getting warmer with sunshine; however, my grammatophyllum was doing fine until the warm day 70~55F.
I found it starts having brown leaves all over the top (it looks like the sun burnt where ever is not covered), I think it is sunburn, but not so sure because it was a warm day not a hot day, and other cattleya and vanda, even my ctsm witchcraft were doing pretty good.
furthermore, I read a lot of info they all suggest gramma can grow in full sun happily so is it somekind of cold damage, rot or infection?

I hope someone can give me some advices, very appreciated, and happy new year.