Help on AR Customer Balance != to Aging Balance

Hi Guys,

I created an ar aging sql with additional details, what i dont understand is why my total amount does not equal to the standard report ar aging total amount.

My query does match the customer balance in ocrd.

SELECT

  T0.ShortName,

  SUM(T0.BalDueDeb-T0.BalDueCred) as JournalTotal,

  MAX(T2.balance) AS CustomerBalance

FROM JDT1 T0

  LEFT JOIN OCRD T2 ON t2.CardCode = T0.ShortName

WHERE  T2.CardType = 'C'

AND T0.BalDueDeb != T0.BalDueCred

AND T0.RefDate <= GETDATE()

  AND T0.IntrnMatch = 0

GROUP BY T0.ShortName

The balance due in ar aging is smaller, for example, some do match but not at all.

the version is 9.1 pl06

I compared the documents in standard ar aging some documents refer to ContraAct, some Shortname

anyone know why my balance does not match? the demodb works fine at all

thanks in advance