They may be in the process of upgrading their useability with IE11, Firefox and other browsers. I was having problems checking my RPAL status a couple months ago because there is a point where you have to enter some info and 3 security questions. It wasn't allowing me to do it, so I called and the lady told me that the site was written in IE 9 or something and they were planning to update it soon to be more versatile. She told me to get past that point of the account creation I had to go into F12 Developer Tools in the Tools Menu and run my IE11 as IE 9. Not saying this is your problem, but they may have the site down if they are trying to start with the update....
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