Manually creating /item/refund

Hi,

I am trying to manually create /item/refund using below opcode:

r << e 1

0 PIN_FLD_POID           POID [0] 0.0.0.1 /account 4965430 0

0 PIN_FLD_BILLINFO_OBJ   POID [0] 0.0.0.1 /billinfo 4935611 0

0 PIN_FLD_PROGRAM_NAME    STR [0] "Manual Refund Entry"

e

xop PCM_OP_BILL_ITEM_REFUND 0 1

but while invoking this am getting the below error,why is it so ?

xop: opcode 925, flags 0

XOP "925" failed: err 37:PIN_ERR_TRANS_ALREADY_OPEN, field 0/16:PIN_FLD_POID,

        loc 6:PIN_ERRLOC_FLIST, errclass 1:PIN_ERRCLASS_SYSTEM_DETERMINATE, rec_id 0, resvd 0

# number of field entries allocated 20, used 2

0 PIN_FLD_POID           POID [0] 0.0.0.1 /account 4965430 0

0 PIN_FLD_ERR_BUF         ERR [0]

        <location=PIN_ERRLOC_FLIST:6 class="PIN_ERRCLASS_SYSTEM_DETERMINATE":1 errno=PIN_ERR_TRANS_ALREADY_OPEN:37>