The certifications are do not renew automatic.

[mikaeakerlund]

I have two servers with same problem. Im using the cronjob as in the description. But every third month i need to restart the server to get the certification to renew. Anyone else with this problem that can help me found a solution?

[codethirteen]

I've been having the same issue for a few weeks on two seperate servers running Ubuntu 16.04 as well. The script runs nightly but returns a not-needed message:

The following certs are not due for renewal yet:
  /etc/letsencrypt/live/example.com/fullchain.pem (skipped)
No renewals were attempted.

The quick and dirty fix is to add --force to the renew command. So in crontab you'll have something like:

For Ubuntu 16.04 and 18.04

0 */12 * * * letsencrypt renew --force && service nginx-sp reload