I am pretty sure that is not an error message from Let's Encrypt. That looks more like something issued by the ACME Client itself. A couple quick searches finds similar error messages related to Traefik.
Sometimes ACME Clients pre-check the cert request before sending it to LE. This looks like that kind of failure. Sorry but I don't know Traefik well enough to be specific.
The LE server would not look at the A or AAAA record for a DNS Challenge. Only a TXT record.