temp usage question

 our customer have db 11g ,

they set temp tablespace size  32G.

but in application ,they still find  " unable to extend temp segment by 128 in tablespace  temp";

i give them such sql

check sort segment:

select TABLESPACE_NAME,TOTAL_BLOCKS,USED_BLOCKS,FREE_BLOCKS from v$sort_segment;

check sql in sort segment:

SELECT a.username, a.sid, a.serial#, a.osuser, b.tablespace, b.blocks, c.sql_text
FROM v$session a, v$sort_usage b, v$sqlarea c
WHERE a.saddr = b.session_addr
AND c.address= a.sql_address
AND c.hash_value = a.sql_hash_value
ORDER BY b.tablespace, b.blocks;