dobrosavljevic,
Is this cron job created with the creation of a new LE certificate? I have a handful of installations that suffer from this issue too. I just checked a system that reported today that the cert would expire in 19 days. When I checked the system, sure enough, the cron job was missing so I added this to my crontab for the user “asterisk”. The certificate immediately when the cron job ran.
Like many others, I have just been fixing these by hand in a one-off fashion because it is an easier fix than to report it. Thanks for pointing this out and sharing the knowledge!!