Series Field can't be selected in Chart

[yinsw]

PHPMaker v2024.9

I choose Stacked Column 2D Chart.

No matter what field I choose in Series Field, it will show "The field '<fieldname>' cannot be used for series.". The field is correct but I cannot choose it. Why?

[arbei]

Not all fields can be used as series field.

1. What is the typoe of your report? Crosstab or summary?
2. What is the field type? If the field is Row Heading field in Crosstab Report or Grouping Field in Summary Report, and the chart's X axis field is also a Row Heading or Grouping field, then the Series field must be of lower level than the X axis field.