[Kotlin] Points not being drawn (Realtime)

[BerkDelivers]

I'm making an API call, and trying to plot the data I get into the graph.
However, when the application runs, there are no points drawn on the graph and the graph is not scrollable/scalable.

There are no errors being logged. Here is how I'm setting up my graph:

graph = view.findViewById(R.id.graph) as GraphView
series = LineGraphSeries<DataPoint>()

Then, in my response parsing method:

for (i in 0 until dataArray.length()-1) {
val point = DataPoint(i.toDouble(), obj.get("value").toString().toDouble()) series!!.appendData(point, true, dataArray.length()-1)

This is what I end up with:

Am I doing something incorrect to load these data points in?