Error Code 429 using NodeJS Plotly Library

I was using the node api for a few months while developing my app: Getting started with plotly in Nodejs

However, randomly yesterday the API calls to plotly started returning a Error Code 429.

I read over the rate limits and feel there is no way I am over the limit Chart Studio API rate limits

I am creating the plotly object in node like this

var plotly = require('plotly')('USERNAME', 'API_KEY');

and then I only call plotly.getImage

Any idea how to debug this API key issue?