ObsGraph shows wrong chart with mismatched observations for concepts given a concept with missing obs

Background

We are using ObsGraph with multiple concepts. But all concept may not have observations at some times. For example,

ObsGraph has 2 concepts configured say Score-1, Score-2. Some time observations available only for Score-2 but not for Score-1. On this situation, the ObsGraph shows Data of Score-2 as Score-1 data and plots the chart.

Fix

Removing series for concepts whose corresponding data points are missing will resolve this.