ACME 404 errors for existing end-to-end tests: “No such authorization” / “Certificate not found”

same here, we are getting 404 sometimes when trying to finalize an oder:
urn:ietf:params:acme:error:malformed: Certificate not found
@zak905 posted new thread about this problem here: Getting intermittent 404 from let's encrypt, when finalizing an order - #3 by zak905