Hi Shivaprasad,
let me know one thing here did you get the account group number on your first drop down value or some other..
i will give one class please check that and you have to use like this..
example code:
CALL METHOD cl_crm_uiu_bp_cust_get=>get_val_for_account_group
EXPORTING
iv_activity = gv_activity
RECEIVING
rt_value = lt_ddlb.
INSERT INITIAL LINE INTO lt_ddlb INDEX 1.
IF sy-subrc = 0.
gr_ddlb_grouping->set_selection_table( it_selection_table = lt_ddlb ).
ENDIF.
provide the screen short for better understand along with component details..
Regards,
Srinivas.