I would be interested in a link to that notion, because such a thing does not exist, not from Let's Encrypt at least: all certs are the same and all certs are free, as in, free beer.
Also, you have issued 5 certificates for hldvy.com which has triggered the " Duplicate Certificate limit of 5 per week". Earlier, you requested and got issued a (single) cert for the base domain as wel as the www subdomain. I would strongly recommend to get a cert with both those hostnames, as otherwise your www subdomain wouldn't work.