create custom form (screen) change delivery block sales order

[former_member407037]

please am new on abap i have create form in custom workflow to display this form in manager inbox

to approve the change on block delivery

when press button approve delete block delivery from sales order

appriciate your help

ZWS800003860001
FORM export_data_0001
   USING ps_data_structure TYPE any.


* move data from the structure to the container
  CALL FUNCTION 'SWY_STRUCTURE_TO_CONTAINER'
    CHANGING
      data_structure = ps_data_structure.


           DATA : is_sales type zsales.        
DATA: BAPISDH1 type BAPISDH1.
                 ok_code type sy-ucomm.
           ok_code = sy-ucomm.
           Case ok_code.
             when 'APRV'.
               is_sales-sales = ps_data_structure.
               modify zsales from is_sales.
            set  BAPISDH1-DLV_BLOCK = ''.
               commit work.
               leave program.
               when others.
                 endcase.
 ENDFORM.      


i need to use in  
CALL FUNCTION 'BAPI_SALESORDER_CHANGE'     in above script to edit 

BAPISDH1-DLV_BLOCK = ''