Have you made an usually large number of reports in the past month? (I mean, unusually for you.) I get the same
error trying to access my Ignore list due to having ignored thousands of users (actually it's probably in the tens of thousands now, but I have no way of checking due to not being able to access the page).
Yes, this month was a record one for me. I have sent over 20 000 reports in the last 30 days. I think I have reached some certain internal memory limit (or something like that) and now this page is completely inaccessible to me. Previously, I had never sent such volumes of reports, so everything always worked properly. Recently, the report history page has been taking a very long time to load despite a constantly stable internet connection. I think it's somehow related.
I wrote about the problem to the administrator. Maybe he can clean up my crowded history.