Access List: Blocked by X-Frame-Options Policy

We've had intermittent problems over the past year with being able to get to the access list.

Advanced tab > Security > Access Control sometimes "Blocks" our devices on its own. (Not sure how).

Advanced Setup>Wireless Settings>Setup Access List> when you go to add or edit either wants to direct us to a weird [URL] in brackets or says "Blocked by X-Frame-Options Policy"

We've tried restarting a few times.

How can we get back into the access list and what is going on?

Firmwar version is 3.01.22 and we're on Comcast.