SSRS display group value under group header

Question

I have the following data in my table:

GroupID | StaffName
-------------------
  G1    |   Alex
  G1    |   James
  G2    |  William

Then I want to Group them by GroupID. I have try using "Add Group -> Adjacent Before". But the result as below:

But what I want is as below:

How to I achieve this? Thanks

Answer 1

I solved the issue as following step:

1. Right click detail and select "Group By -> Add Parent Group -> Select GroupID".
2. New group column will auto generated, and a new row will auto generated at above StaffName.
3. Select GroupID at new generated row, same column with StaffName.
4. Delete the extra column.

Finally work!