Reconcilliation Process Issue

 Hi Folks,

Our user will upload Lines through data loader as bank statement, and trying to do manual reconcilliation,

i.e lines created and status as "Unreconcilled" date ex: 15-Jul-2010. this transaction is not available in the system when he upload,

after few days he will enter the payment or journal date as "20-Aug-2010" and try to select the transaction it is showing formexception error.

so how we can resolve this error.