too many certificates already issued for exact set of domains

docker images: latest os centos 7.6 docker version: 1.13.1 I run the commad:

docker run -d -v `pwd`/caddy/Caddyfile:/etc/Caddyfile --name=caddy --net=host -e CLOUDFLARE_EMAIL="13722926737@163.com" -e CLOUDFLARE_API_KEY="1235612" docker.io/abiosoft/caddy

The Caddyfile:

www.cphcm.tk:443 {
  root /srv
  proxy /ray localhost:123456 {
    websocket
    header_upstream -Origin
  }
  tls {
    dns cloudflare
    }
}

The logs:

[root@c2 v2ray]# docker logs -f caddy/
Activating privacy features... 2019/10/15 02:34:41 [INFO][cache:0xc00008a820] Started certificate maintenance routine
Your sites will be served over HTTPS automatically using Let's Encrypt.
By continuing, you agree to the Let's Encrypt Subscriber Agreement at:
  https://letsencrypt.org/documents/LE-SA-v1.2-November-15-2017.pdf
Please enter your email address to signify agreement and to be notified
in case of issues. You can leave it blank, but we don't recommend it.
  Email address: 2019/10/15 02:34:46 [INFO][www.cphcm.tk] Obtain certificate
2019/10/15 02:34:46 [INFO] [www.cphcm.tk] acme: Obtaining bundled SAN certificate
2019/10/15 02:34:46 [ERROR][www.cphcm.tk] failed to obtain certificate: acme: error: 429 :: POST :: https://acme-v02.api.letsencrypt.org/acme/new-order :: urn:ietf:params:acme:error:rateLimited :: Error creating new order :: too many certificates already issued for exact set of domains: www.cphcm.tk: see https://letsencrypt.org/docs/rate-limits/, url:  (attempt 1/3; challenge=dns-01)
2019/10/15 02:34:47 [INFO] [www.cphcm.tk] acme: Obtaining bundled SAN certificate
2019/10/15 02:34:48 [ERROR][www.cphcm.tk] failed to obtain certificate: acme: error: 429 :: POST :: https://acme-v02.api.letsencrypt.org/acme/new-order :: urn:ietf:params:acme:error:rateLimited :: Error creating new order :: too many certificates already issued for exact set of domains: www.cphcm.tk: see https://letsencrypt.org/docs/rate-limits/, url:  (attempt 2/3; challenge=dns-01)
2019/10/15 02:34:49 [INFO] [www.cphcm.tk] acme: Obtaining bundled SAN certificate
2019/10/15 02:34:50 [ERROR][www.cphcm.tk] failed to obtain certificate: acme: error: 429 :: POST :: https://acme-v02.api.letsencrypt.org/acme/new-order :: urn:ietf:params:acme:error:rateLimited :: Error creating new order :: too many certificates already issued for exact set of domains: www.cphcm.tk: see https://letsencrypt.org/docs/rate-limits/, url:  (attempt 3/3; challenge=dns-01)
2019/10/15 02:34:51 failed to obtain certificate: acme: error: 429 :: POST :: https://acme-v02.api.letsencrypt.org/acme/new-order :: urn:ietf:params:acme:error:rateLimited :: Error creating new order :: too many certificates already issued for exact set of domains: www.cphcm.tk: see https://letsencrypt.org/docs/rate-limits/, url: 
exit status 1

The damain have many certificates, how can I revocation certificate ？

abiosoft / caddy-docker

too many certificates already issued for exact set of domains #227

The logs: