Roll Back Problem after Calling GN_DELIVERY_CREATE FM

Hi experts !

I want to create an outbound delivery for a document with 3 items , but for one of these items ,there is a problem for exp.After calling  GN_DELIVERY_CREATE Function , the function create a document in likp with 2 items , but steel

there is a problem for the last item , a problem is : the function doesn't show which item have problem and for

which items it created a delivery , but there is a table  xvbfs , whenever the function have a problem this

table is not empty and there is a record with status 'E' .

for solving this problem after calling the function I check is this table initial or not and if the table xvbfs is not initial

i try to roll back , but the roll back didn't work , and the record still exist in likp and lips table , the calling form of this

Function is like this :

CALL FUNCTION 'GN_DELIVERY_CREATE'

     EXPORTING

       vbsk_i                   = wa_vbsk

       vbls_pos_rueck           = 'X'

       if_no_deque              = 'X'

     TABLES

       xkomdlgn                   = it_komdlgn

       xvbfs                      = it_vbfs

       xvbls                      = it_vbls

       xxlips                     = it_lips

       it_gn_partner              = it_partner.

   P_ERR = Zkkk=>GET_Msg( P_VBFS = IT_VBFS ).  " this method will return the error message

   IF P_ERR IS NOT INITIAL.

     ROLLBACK WORK .

     LOOP AT P_ZMTC into wa.

       ME->__MARK_AS_ERROR( P_ERR_MSG = P_ERR  P_WA = WA ). " all records will update with 'E' status because  I don't know which record

                                                                                                                  have a problem.

     ENDLOOP.

   ELSE.

thank you for the time .