Norton DNS not working.. :(

use a long time norton DNS and so happy for your idea but, not working two weeks your dns. I can not enter web sites and not use windows/android apps when I add your dns on my router or pc. there was no problem until two weeks ago, will we not be able to use in Turkey and why?

help me please, if I can not use norton DNS, I feel i’m not safe…

have a nice day