Why are we not able to confirm payment against the Voucher transaction?

Cause:
While confirming the payment against the voucher system showing the “The voucher does not have sufficient balance”. If Voucher already adjusted in payment transaction. Then the system will not allow the user to adjust the same voucher amount in another payment. So the system showing vouchers does not have sufficient balance.
Suggestion:
Users need to ensure that the voucher selected should be pending for payments. System will adjust the voucher which is pending.