Data issue

Hello Experts,

we are developing webi reports on top of bw query, we are facing strange behavior in webi report,the data is shifting the columns,example, i have sales document,document type,material,reason codes and value in the report, some times the data is populating correctly and some times its shifting the columns,meaning in sales document column i see document type or materail or in material column i see document type and all, please help me with the issue.

thanks.