Server REST API Not Working

I have followed the rough guide posted on https://support.iridiummobile.net/topics/283-server-rest-api/ and have failed to get any feedback from the server on the port 8443. When I switch to port 8888 on HTTP I make some progress, but most payloads are always returned blank.

For example the following request and response are typical.

http://172.16.1.250:8888/json/licence/get

{
    "type": "",
    "script_mode": "",
    "qr_mode": "",
    "server_max_clients": "",
    "datapoints": "",
    "serial": "",
    "expired": "",
    "products": []
}

My requirement is to change a driver value via the API; but so far I feel like I am missing an authentication step. Any guidance please?

thanks

Damian

BTW -

http://172.16.1.250:8888/plain/licence/get  returns a 404