WBS closed without settling the cost in AUC

Hai

One WBS was closed wihout settling the AUC value. How system allowed to close without final settlement of cost.

While re-opening of WBS from status CLSD to TECO, system is showing following message without updating the status.

Update was terminated

System ID....   SRP
Client.......   999
User.....   CT PS1
Transaction..   CJ20N
Update key...   51B045DC58421140E10080000A100140
Generated....   14.06.2013, 15:59:36
Completed....   14.06.2013, 15:59:37
Error Info...   ABAP/4 processor: SAPSQL_ARRAY_INSERT_DUPREC

Now FI persons are worrying for non settlement of cost in AUC.

Please suggest how to reopen the WBS.

with regards

M Umapathy