Why I'm unable to change a default logo (JNews) and add my custom logo?

Sorry if I’m in the wrong room, but this thing frustrates me.
I have been trying to change a logo for days now, but I fail. I tried to my level best, even by adding the codes to the header.php but nothing displays as I want. Now I can’t change logos, to Featured Images not showing. Its been a week and I am already tired of this theme called JNews.

Can anyone help me out on how to change a logo and bringing ‘‘Featured Image’’ option back to work?

Thanks.

Truly frustrating L-O-L

Hi @offblogmedia,

Please contact the author of your purchased theme, the theme author will assist you.

How to contact an author to get support or for any technical query:

Thanks