how to unapply and then re-apply invoice to receipt using AR_RECEIPT_API_PUB?

I need to implement partial refund of prepayment.

The scenario is :

- unapply invoice/prepayment;

- apply debit memo;

- reapply invoice/prepayment for remaining amount.

This scenario works fine from UI Receipts>Applications screen, but when I unapply invoice/prepayment programmatically using AR_RECEIPT_API_PUB.unapply or AR_RECEIPT_API_PUB.unapply_other_account, this invoice/prepayment cannot be anymore applied , it cannot be seen in Open Items LOV.

Status is Closed in ar_payment_schedules_all.

I would appreciate any suggestions how to handle this very much.

Thanks,

Asnate