Why is my logo missing logo on home page? (with site)

Why is my logo missing logo on home page?

I have just noticed that the logo we had in the top left of our home page (and all pages ie above the tab strip) is missing.

I am not sure how to get it back as I am not sure why it disappeared.

Can someone please advise?

Thanks.
Karen

My site is http://www.publicaffairsjobs.com.au

PS When you list the query it says click here to view or EDIT your support request - there is no where to edit the request, hence the repost.