Loans Management - Closed Contract

Dear Expert.

Is there any validation that i can set while using tcode FNV2; current program, system still allow to changed to 'closed contract' while there is still balance outstanding in cash flow.

Table VDARL-SSTATI

How to make sure program can validate whereby if the contract still have the outstanding balance, it cannot be set to closed.

Need your kind advice and comment.

Thank You.

Best Regards