nknd report error on the control console.the log is:
[ERROR] GID 148, apply cert failed: 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: nknlabs.io: see https://letsencrypt.org/docs/rate-limits/, url:
Our technical team informed us that the letsencrypt certificate limits have been increased. Please let us know if such error persists.
This is a nice information, 
This error still persists.
2021/04/18 23:13:39 [INFO] [[redacted].ipv4.nknlabs.io] acme: Obtaining bundled SAN certificate
2021/04/18 23:13:39.930321 [ERROR] GID 55, apply cert failed: 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: nknlabs.io: see https://letsencrypt.org/docs/rate-limits/, url:
2021/04/19 08:44:00 [INFO] [125-71-150-92.ipv4.nknlabs.io] acme: Obtaining bundled SAN certificate
2021/04/19 08:44:01.330969 [ERROR] GID 43, apply cert failed: 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: nknlabs.io: see https://letsencrypt.org/docs/rate-limits/, url:
Hi, I’m new with the nkn thingy. Is there a solution now? Have the same problem 
2021/04/24 20:10:36.642692 [ERROR] GID 47, apply cert failed: 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: nknlabs.io: see https://letsencrypt.org/docs/rate-limits/, url: