Combination chart containing zeroes terminates prematurely

Hi I created a views chart with a chart addon using the SQL date formatter module which works very nicely. Added an exposed date filter as well.
But for some datasets, the addon part terminates prematurely. I am assuming this is because there is a zero value at that interval and charts doesnt know how to continue from there. I dont know. Here is a chart showing a monthof data and notice it stops:

but if you adjust the filter to one week, it proves there is data for the last 7 days, but charts module gave up on 29th of last month, and also quit on the 15th of this month. I can confirm there is no data for the sixteenth but there is for the 15th and 17th onwards.

Any thoughts? How can I get charts to plot zero where there is no data, and continue on?