How to create a line chart to add to a report?

There are some pretty charts in fortianalyzer and I want to be able to include them in my custom reports, but keep failing to create them. For example here is a chart from Top destination for a specific host: basic_1.jpg Just the number of sessions in a given time.

I want it to be in my report, so I go to Export to Report chart - then to reports - edit this chart and choose Line instead of Table in Char type but whatever data binding I choose all I get is a blank chart. Same for the Bar chart, just no data in it. Obviously I'm doing something wrong but I dont get what exactly. How do I build a chart like in basic_1.jpg?