Sql Query Error "ORA-01403: no data found"

Question

I have query to get value from an Oracle database to SQL Server table, and here's my code :

SET @TDATE = GETDATE()
SET @DDATE = CASE @DDATE WHEN '' THEN CONVERT(VARCHAR(10),GETDATE(),121) ELSE @DDATE END

SET @sQuery = 'SELECT * INTO ##TMPWIP FROM OPENQUERY(ITCP,''SELECT * FROM DBW.VAAPX9 WHERE SCH_DATE = '''''+ CONVERT(VARCHAR(10),@DDATE,121) +''''''') A'

EXEC(@sQuery)

actually it never give me an error but today I got an error :

OLE DB provider "OraOLEDB.Oracle" for linked server "ITCP" returned message "ORA-01403: no data found".

but if I query the Oracle database, it returns the result so there is data.

I'm new in writing queries between SQL Server and Oracle, and the issue just happen today, what's wrong with my code?