获取证书失败 Ubuntu 18.04 x86_64

[cr.z]

Performing the following challenges:
http-01 challenge for www.xxx.top
Waiting for verification...
Challenge failed for domain www.chewyee.top
http-01 challenge for www.xxx.top
Cleaning up challenges
Some challenges have failed.

IMPORTANT NOTES:

• The following errors were reported by the server:

  Domain: www.xxx.top
  Type: dns
  Detail: During secondary validation: DNS problem: SERVFAIL looking
  up CAA for www.xxx.top - the domain's nameservers may be
  malfunctioning

• Your account credentials have been saved in your Certbot
  configuration directory at /etc/letsencrypt. You should make a
  secure backup of this folder now. This configuration directory will
  also contain certificates and private keys obtained by Certbot so
  making regular backups of this folder is ideal.
  获取证书失败，请到 https://www.hijk.pw 反馈

[hijk]

域名的dns设置有问题