"Manage" Button for WebSite Security Does Not Work

I am getting so tired of calling in to Support every time I need my firewall cache flushed. The "Manage" button takes me to an about:blank page. This has been going on for almost two months now, and it's getting very tiresome. Sometimes when I call in, the support person tells me that they want to tell me how to flush the cache. I know how to flush the cache. I just can't get to it. Every other button on the page takes me to where I want to go, but not this one!

Yes, I have used four different browsers, Opera, Firefox, Edge and Chrome and flushed the caches (which I do routinely anyway). Is there a solution to this problem?