Before I answer to your question I'd like to specify something. I saw that your business data defines DataTime and integer types, in this case you should use Line Series
instead of Scatter Line Series (the scatter series require both axis to be linear), whose axes are Linear and Logarithmic. More about the axes supported by each ChartView series you can find in our help topic - Series and Axes
So, about the continuous line you want to represent - the Line Series are rendered using a collection of points connected by straight line segments. When the value of the DataPoint is Null, this is represented as a gap. So, you should have at least 2 points with some value to see the representation of the Line Series. However, if you want to see a continuous line you can replace the empty values with zeros or you can sort your data so that there is no items with null values.
I hope this information will help you and don't hesitate to write back if you have more questions.
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