How to find Uniqe Account for Service Request

Hi Gurus,

We have a Inbound webservice in our development environment that create Service Request record. And we are using vanilla Business services to expose as a web service.

Th input consists of Account Name, Contact First Name, Contact Last Name and other SR details.

In out environment, Account Name is not unique, so webservice is not able to find unique Account to create SR. And so let say Account Name is CitiBank and if there are two accounts with that name in Siebel, then it is creating a SR in the Account which has oldest created date.

We have a unique Account number where we store in OU_NUM column and that field is existed in Service Request BC & SR Integration Component also.