Debit balance has not been adjusted while APP F110 Paymemt Run

Hi Expert,

i have given Number Range for Vendor Payment as on 06.08.2015 Account from 5000 to 7000

only i have select only 5060 where total Outstanding Balance was INR 8949.00

Invoice Amount was 12656.00(-)

Debit Note                3707.00

To Pay 8949.00 if i Run .. and i select Edit n choosen Line item system asking against which Line Item i have select 12656.00  but two line item was showing one is debit  i.e 3707.00 another is Credit.i have select  the same amount i.e 12656.00 .. where i have done mistake to give the payment.

i have select 12656.00 line item double click and asking Payment Method i have given all the parameters Payment Method "C" House Bank "BOM"

Account ID "1000"

but my doubt is why system taken 12656.00  should be Minus from Debit Balance and give remaining Payment i.e 8949.00

Thank You!

Pranav