Alv OO program error Message no. 0K534

Hi expert,

        Everytime i hit enter or any command button the program prompt me an error message

even though i already declare all my variables globally still the error is the same.

my global variable Declaration

DATA: gr_data     Type Ref To DATA.
          DATA: la_data     Type Ref To data.
          FIELD-SYMBOLS: <gt_data> TYPE STANDARD TABLE.

my Full source code.

me->get_data( CHANGING c_data = <f_tab> ).

METHOD get_data.

       GET REFERENCE OF c_data INTO la_data.
       move la_data TO gr_data. " pass to global variable

        assign gr_data->* to <gt_data>.
         IF gc_custom_container is initial.
           CREATE OBJECT gc_custom_container
               EXPORTING
                  container_name  = gv_mycontainer.
         ENDIF.

         if table is not bound.
            try.
                "// Create ALV Instance
                cl_salv_table=>factory(
                  exporting
                    r_container    = gc_custom_container
                    container_name = 'TC_MIXING'
                  importing
                    r_salv_table   =  table
                  changing
                    t_table        = <gt_data>
                 ).
              catch cx_salv_msg.                              "#EC NO_HANDLER
            endtry.

           "// Setup ALV Attributes
           functions = table->get_functions( ).
           functions->set_all( abap_true ).

           columns = table->get_columns( ).
           columns->set_optimize( abap_true ).

           try.
               column = columns->get_column( 'MANDT' ).
               column->set_technical( if_salv_c_bool_sap=>true ).
             catch cx_salv_not_found.                        "#EC NO_HANDLER
           endtry.
           "// Dispalay ALV Model
           table->display( ).

         else.
           table->refresh( ).
         endif.

ENDMETHOD

Any suggestions?

Thanks.