Thanks for reaching out, and welcome to the Netlify Forums!
So this error essentially means “we tried to make a wildcard certificate since you have DNS hosting enabled. However, the DNS record we made was not found by lets encrypt, so provisioning failed.” What this means is that you have an inactive DNS zone that you will need to disable before we can extend the certificate to your site.
You can follow this support guide to walk through deleting inactive DNS:
Thanks for the quick reply and the link to the support guide.
I’m a little confused though because I’m not sure if the DNS zone mentionned is the Netlify one or the one from the external register of the custom domain?
dig coreevoyage.fr NS +trace | tail -n 6
coreevoyage.fr. 3600 IN NS dns1.p04.nsone.net.
coreevoyage.fr. 3600 IN NS dns4.p04.nsone.net.
coreevoyage.fr. 3600 IN NS dns3.p04.nsone.net.
coreevoyage.fr. 3600 IN NS dns2.p04.nsone.net.
;; Received 132 bytes from 22.214.171.124#53(dns2.p01.nsone.net) in 20 ms