Cetificat wen ubuntu 18-04 lts server speedtest

I’ve continue to help investigate: Configuration du certificat pour mon server web

The problem is definitively with the DNS resolver:
dig @8.8.8.8 acme-v02.api.letsencrypt.org works
dig acme-v02.api.letsencrypt.org doesn’t works
dig www.google.com works
Anybody have an idea how to investigate further ?