Prepaid Voucher is not applied on reguler voucher if Wihtholding is postponded on Prepaid Voucher an

Suppose there is a supplier abc on which Withholding is applicable (suppose 4%)

Now I create a prepaid voucher of Rs. 10,000 for this supplier. I postpone the withholding on this voucher and pay the voucher.

Now I create a reguler voucher for this supplier for suppose Rs. 5,000. I have to apply withholding on this voucher.

After creating the reguler voucher I post the reguler voucher, Consiquentily withholding is seperated from payment but Pre-paid voucher is not applied on this voucher.

When I try to manually apply prepayment on this voucher system through an error that withholding has already been calculated on this voucher, to apply prepeyment unpost voucher and then apply prepayment.