Removing a photo from a page

I have a photo that I have been using for 6 yrs now and stated was not copyrighted when I 1st used it (although I do see it in other places). I have now been contacted that is is copyrighted, buy it or remove it it, blah, blah blah. It is on one of my pages that was built with page builder. I have removed it from the gallery and now have a blank box that says Belize in the left top corner and a tiny little picture icon (like when your connection won’t read a picture). I want to remove that box and add another picture but can not figure out how to edit the pictures in that left side bar. Thank you in advance for your help! Marie

URL: http://www.liquidbluetravel.com/group-programs/