I don't have any good advice. This is a very odd error. You might try posting on the Certbot github to reach their devs more quickly.
There was a similar error about a month ago at below thread. But, no other threads with similar error since a couple back in 2016-2018.
I changed your thread title to focus more on this specific error.
I saw you got 2 Staging certs earlier today. Is this error only on production ?