Issue Solved... Thanks for your help. issue is in IF statement.
Old Stmt:
---------------
IF so_werk = '1061'. " Problem is here"
SELECT a~werks a~budat a~qualf a~urcod a~arbpl a~katalogart a~urgrp a~urcod a~version
a~iserh
INTO CORRESPONDING FIELDS OF TABLE itab1
FROM zctsi_pw AS a
WHERE a~werks IN so_werk
AND a~budat IN so_budat
AND a~arbpl IN so_arbpl
AND a~aufnr IN so_aufnr
AND a~urgrp IN so_urgrp
AND a~urcod IN so_urcod.
ELSE.
***
***
ENDIF.
New Stmt:
----------------
IF so_werk-low = '1061'.
SELECT a~werks a~budat a~qualf a~urcod a~arbpl a~katalogart a~urgrp a~urcod a~version
a~iserh
INTO CORRESPONDING FIELDS OF TABLE itab1
FROM zctsi_pw AS a
WHERE a~werks IN so_werk
AND a~budat IN so_budat
AND a~arbpl IN so_arbpl
AND a~aufnr IN so_aufnr
AND a~urgrp IN so_urgrp
AND a~urcod IN so_urcod.
ELSE.
***
***
ENDIF.