Not able to modify the column name in the combination chart

[avik1986]

The highlighted legend name is the measure showing values. User needs different name. I changed the data item name, label name but it is showing the table column name. Please find the attachment.

[Drisya]

Select the measure name in the graph then in properties, change the source type to 'Data Item Label'.
Now run the report and see if the name matches with label given.