Your anchor (link) is formatted OK (just copy the code to a blank page and you will see that it works fine) and the image element should have a "/" before the close of the element, but that is not the problem here.
I took a quick look with my browser's developer tools and found that for some reason your anchor "<a>" element for this particular link is styled with a width of 180px and height of 15px.
I dont have time at the moment to go through your Styles to see if you are placing this element behind the div or something similar, but that is what I suspect your problem is.
I haven t had a chance to look deeper, but I can tell you when I was using the built in dev tools in the browser, when I clicked on the anchor tag in te source, those where the properties shown o the screen. It didn't look right. If you copy the code on its own page, it works fine. This appears to be a styling problem.