Newly created F4 Help not working

Dear Experts,

I have generated GET_V method for my input field. I made the below code. But my break point is not triggering while clicking the field. Anyone guide me.

At the same time, if I open transaction ( BSP_WD_APPL_WB_NEW ) to cross check my coding in GET_V method in another screen, that time the break point getting triggered. It’s a strange behavior, hope I made some mistake so any one can guide me.

METHOD get_v_r3mat_id.
  DATA :

        ls_map TYPE if_bsp_wd_valuehelp_f4descr=>gtype_param_mapping,
        lt_inmap TYPE if_bsp_wd_valuehelp_f4descr=>gtype_param_mapping_tab,
        lt_outmap TYPE if_bsp_wd_valuehelp_f4descr=>gtype_param_mapping_tab.

  ls_map-context_attr = 'STRUCT.R3MAT_ID'.
  ls_map-f4_attr = 'PRODUCT_ID'.
  APPEND ls_map TO lt_inmap.
  CLEAR ls_map.

  ls_map-context_attr = 'STRUCT.R3MAT_ID'.
  ls_map-f4_attr = 'PRODUCT_ID'.
  APPEND ls_map TO lt_outmap.

  CREATE OBJECT rv_valuehelp_descriptor TYPE cl_bsp_wd_valuehelp_f4descr
    EXPORTING
      iv_help_id        = 'CRM_ISU_PRODUCT'
      iv_help_id_kind   = if_bsp_wd_valuehelp_f4descr=>help_id_kind_name
      iv_input_mapping  = lt_inmap
      iv_output_mapping = lt_outmap.


ENDMETHOD.