Watcher for monitor a process does not work

Elastic Stack Kibana
2

Take a look at your watcher history to see what might be going on. For example:

GET .watcher-history-*/_search?size=100
{
  "sort" : [
    { "@timestamp": "desc"}
  ]
}

If nothing stands out there, enabled debug logging for watcher, and see what is in your logs. For example:

PUT /_cluster/settings
{
  "persistent": {
    "org.elasticsearch.xpack.watcher": "DEBUG"
  }
}

Another thing to check is your SMTP server log -- several times I have seen a problem in the SMTP server, and Elasticsearch won't know anything about that.