How to do refund of deposit amount in r12?

 Hi All,

User entered deposit transaction (No: 125501) and amount is 40000. 40000 receipt is applied to that deposit. Now user entered an invoice (No: 241001) for 32000 and that deposit (125501) applied to that invoice.

For remaining 18000 user wants refund to the customer. Here system not allowing the user to do refund for 18000 because already receipt fully applies to the deposit (125501).

Please suggest us to achieve this.

Thanks in Advance,

Venky.