Navigation issue

Hello,

I wrote an ABAP report which display BOMs in an ALV list. I also have write some code for double click at an ALV line, so that the user when double clicks a line, the corresponding BOM is displayed.

My problem is with the "Back" button. Instead of going back to the ALV list it goes back to the main screen of SAP. Why is that ?

Here is the code for double click:

CLASS GCL_HOTSPOT_HANDLER DEFINITION.
  PUBLIC SECTION.
    METHODS:
      HANDLE_REPORT

        FOR EVENT DOUBLE_CLICK OF CL_SALV_EVENTS_TABLE
          IMPORTING
            ROW
            COLUMN.
ENDCLASS.                

CLASS GCL_HOTSPOT_HANDLER IMPLEMENTATION.

*Method used for handling navigation
  METHOD HANDLE_REPORT.

    CLEAR: GW_CSIN, GW_WU_LIST.
    READ TABLE GT_WU_LIST INTO GW_WU_LIST INDEX ROW.
    MOVE-CORRESPONDING GW_WU_LIST TO GW_CSIN.
    GW_CSIN-DATUB = P_DATUB. GW_CSIN-DATUV = P_DATUV.

    GW_CSIN-CMODE = '08'.
BREAK-POINT.

    IF GW_WU_LIST-VWALT IS INITIAL.
      GW_CSIN-STLAL = '01'.
    ELSE.
      GW_CSIN-STLAL = GW_WU_LIST-VWALT.
    ENDIF.

    GW_CSIN-STUEZ = GW_WU_LIST-STPOZ.
    GW_CSIN-TRTYP = 'B'.

    CLEAR: GW_CSIN-AENNR, GW_CSIN-EMENG, GW_CSIN-POSNR, GW_CSIN-STPOZ.
	
    CALL FUNCTION 'CS_DI_INIT'.
	
    CALL FUNCTION 'CS_BOM_CALL_DIALOG'
      EXPORTING
        ECSIN  = GW_CSIN
        EDYNNR = '0120'.

  ENDMETHOD.
ENDCLASS.