There's currently an item in the Reopen Votes review queue here on Meta, but I can't review it. Refreshing doesn't help (it usually does with this error, but not right now):
The call to
next-task fails, it redirects to the error page:
(I've saved that call as a cURL but I'm not sure it's of much use right now.)
A few minutes later, I was able to review a Reopen Votes item, but clicking 'Leave Closed' produced the same error, even though the review itself went through: https://meta.stackexchange.com/review/reopen/68625. The above error still persists.