In the graph, the y-axis does not show its proper scale.Why?

@kumars23

I tried to recreate your problem. The second graph in the image below has a similar issue. As you can see, the Y value has been chosen as the series label since the order of columns in the report a c is Y, X, Y-2.

The first and third graphs have X as the first column in the source report.

So, perhaps your second graph's report has a different order of columns than the first graph's.