A fatal issue occurred during the DNS lookup process for alfa-iso.dk/A.
DNS response for alfa-iso.dk/A did not have an acceptable response code: SERVFAIL
A fatal issue occurred during the DNS lookup process for alfa-iso.dk/AAAA.
DNS response for alfa-iso.dk/AAAA did not have an acceptable response code: SERVFAIL
A fatal issue occurred during the DNS lookup process for alfa-iso.dk/CAA.
DNS response for alfa-iso.dk/CAA did not have an acceptable response code: SERVFAIL
No valid A or AAAA records could be ultimately resolved for alfa-iso.dk. This means that Let's Encrypt would not be able to connect to your domain to perform HTTP validation, since it would not know where to connect to.
No A or AAAA records found.