tradeHistory not working

[simonec1981]

if I liqui.tradeHistory(params).then(result => {console.log(result)});

I get back

Unhandled rejection (<{"success":0,"code":0,"error":"invalid...>, no stack trace).

In my test case I just do the following:

const Liqui = require('node.liqui.io');
then initialize Liqui with my key and secret , then I define params = {pair: 'btc_edg'} and then I do liqui.tradeHistory(params).then(result => {console.log(result)});
I do this directly from node in linux.