Telerik report grouping not showing all data

Question

I am creating a telerik report, in which i applied grouping based on a grouping parameter. (SectionID) thats is bound to a data base table through ObjectDataSource. when i render my report it always shows all records based on First sectionID and not showing all other sectionID(2,3..so on) records.. Below is the example of my output and required output. Please give me your suggestion about how to do it? thanks.

Required Output:

SectionID        ProductName           Code

---

1                  Retail1                 123              
                   Retail2                 456

2                Catering1                 450
                 Catering2                 550

My Output:

SectionID        ProductName           Code

---

1                  Retail1                 123              
                   Retail2                 456