Hi Mohd,
Hope you are using a custom feeder class copied from CL_MDG_BS_MAT_FEEDER_FORM_SET for your initial screen.
Then try redefining method /PLMU/IF_FRW_G_GLOBAL_EVENTS~PROCESS_GLOBAL_EVENT and add below block of code under event 'MDGM_CONTINUE' in your custom feeder class as below. This could work.
DATA: lv_werks TYPE werks_d.
DATA lt_uibbs TYPE if_fpm_ovp=>ty_t_uibb.
DATA lo_cnr_ovp TYPE REF TO if_fpm_cnr_ovp.
DATA ls_uibb TYPE if_fpm_ovp=>ty_s_uibb.
DATA: lo_fpm TYPE REF TO if_fpm,
lo_fpm_ovp TYPE REF TO cl_fpm_ovp.
CASE io_event->mv_event_id.
WHEN cl_mdg_bs_mat_c=>gc_event_continue. " 'MDGM_CONTINUE'
mo_context->get_attribute(
EXPORTING
iv_name = 'YPLANT' " Custom attribute on initial screen
IMPORTING
ev_value = lv_werks ).
IF lv_werks = 'TEST'.
TRY.
lo_cnr_ovp ?= cl_fpm=>get_instance( )->get_service( cl_fpm_service_manager=>gc_key_cnr_ovp ).
lo_cnr_ovp->get_uibbs( IMPORTING et_uibb = lt_uibbs ).
CATCH cx_fpm_floorplan.
ENDTRY.
lo_fpm = cl_fpm_factory=>get_instance( ).
lo_fpm_ovp ?= lo_fpm->get_service('CNR_OVP').
TRY.
LOOP AT lt_uibbs INTO ls_uibb WHERE config_id = 'MDG_BS_MAT_MARA_SALES_05'. " Check for UIBB to hide
ls_uibb-hidden = 'X'.
lo_fpm_ovp->change_uibb(
EXPORTING
is_uibb = ls_uibb " UIBB to be changed
).
ENDLOOP.
CATCH cx_fpm_floorplan.
ENDTRY.
ENDIF.
ENDCASE.