Machine learning API Disabled

The license is apparently active and is of type trial.
{
"license" : {
"status" : "active",
"uid" : "xxx",
"type" : "trial",
"issue_date" : "2017-06-21T14:24:31.620Z",
"issue_date_in_millis" : 1498055071620,
"expiry_date" : "2017-07-21T14:24:31.620Z",
"expiry_date_in_millis" : 1500647071620,
"max_nodes" : 1000,
"issued_to" : "elasticsearch",
"issuer" : "elasticsearch",
"start_date_in_millis" : -1
}
}

There is only one node in the cluster. I am using an elasticsearch-5.4.0 and have the corresponding x-pack version installed. The propertly x-pack.ml.enabled is set to true. This is what I saw in the json response for the node information. Despite the default behaviour, I did update this value in elasticsearch.yml, however, there was still no change.

I could not verify the system clocks. Can you describe this ?

I did not check this before when I installed the x-pack a month ago. I am doing the machine learning with x-pack course offering, which I am doing in the spare time. Until yesterday I wasn't at a point where I needed to actually run a machine learning job. I actually didn't observe the message before.