Negative unapplied receipt

I could see there is a record in my system which has created negative unapplied receipt.But when i try now it says total does not match. My receipt amount is 100 and invoice gross and payment amount is 400.Total unapplied is -300. Now when there is such record already in my system what prevents me to create this. Pls let me know if any setup needs to be done in P03B102 processing option for Negative UNAPPLIED receipt.

Thanks in advance!