Hi Abhishek,
I have reviewed your code, and done changes in it and tested on my system. Now it is working exactly you want. Please use below code.
report ZT5
no standard page heading line-size 255.
include bdcrecx1.
DATA gtvbak TYPE STANDARD TABLE OF vbak WITH HEADER LINE.
data :v_index TYPE char2 VALUE '00'.
data v_string TYPE string.
start-of-selection.
SELECT * from vbak into TABLE gtvbak UP TO 20 rows.
perform open_group.
perform bdc_dynpro using 'ZT3' '1000'.
perform bdc_field using 'BDC_CURSOR'
'SO_VBELN-LOW'.
perform bdc_field using 'BDC_OKCODE'
'=%000'.
LOOP AT gtvbak.
perform bdc_dynpro using 'SAPLALDB' '3000'.
v_index = v_index + 1.
concatenate 'RSCSEL-SLOW_I(' v_index ')' INTO v_string.
IF v_index = 1.
perform bdc_field using 'BDC_OKCODE'
'=P+'.
ENDIF.
perform bdc_field using 'BDC_OKCODE'
'/00'.
perform bdc_field using v_string
gtvbak-vbeln.
IF v_index = 8.
v_index = 1.
IF v_index = 1.
perform bdc_field using 'BDC_OKCODE'
'=P+'.
ENDIF.
ENDIF.
ENDLOOP.
perform bdc_dynpro using 'SAPLALDB' '3000'.
perform bdc_field using 'BDC_OKCODE'
'=ACPT'.
perform bdc_dynpro using 'ZT3' '1000'.
perform bdc_field using 'BDC_CURSOR'
'SO_VBELN-LOW'.
perform bdc_field using 'BDC_OKCODE'
'=ONLI'.
perform bdc_dynpro using 'ZT3' '1000'.
perform bdc_field using 'BDC_OKCODE'
'/EE'.
perform bdc_field using 'BDC_CURSOR'
'SO_VBELN-LOW'.
perform bdc_transaction using 'ZT2'.
perform close_group.