Change Document through cv12 - documents automatically getting deleted

Hello Gurus,

i am trying to create document entries in CV12 using BAPI - BAPI_DOCUMENT_CHANGE2.

But when i try to add single document through BAPI all existing documents are getting deleted automatically and new one getting added and i am not able to see that in CV13.

I have tried by getting all existing documents details using BAPI -  BAPI_DOCUMENT_GETDETAIL2 and pass existing documents along with new document then this is working fine and i can see all documents in CV13.

Please suggest what should i do so existing documents will not get deleted when i pass single document.

i am passing values as below.

ls_docdata-DOCUMENTTYPE    = 'INV'.

ls_docdata-DOCUMENTNUMBER  = '0000000000000010000000134'.

ls_docdata-DOCUMENTVERSION = '00'.

ls_docdata-DOCUMENTPART    = '000'.

ls_docdatax-DOCUMENTTYPE    = 'X'.

ls_docdatax-DOCUMENTNUMBER  = 'X'.

ls_docdatax-DOCUMENTVERSION = 'X'.

ls_docdatax-DOCUMENTPART    = 'X'.

ls_docstr-DOCUMENTTYPE    = 'INV'.

ls_docstr-DOCUMENTNUMBER  = '0000000000000010000000134'.

ls_docstr-DOCUMENTPART    = '000'.

ls_docstr-DOCUMENTVERSION = '00'.

ls_docstr-QUANTITY        = '1'.

append ls_docstr to lt_docstr.

CALL FUNCTION 'BAPI_DOCUMENT_CHANGE2'

   EXPORTING

     DOCUMENTTYPE         = 'FOL'

     DOCUMENTNUMBER   = 'INVOICES'

     DOCUMENTPART         = '000'

     DOCUMENTVERSION  = '00'

     DOCUMENTDATA        = ls_docdata

     DOCUMENTDATAX      = ls_docdatax

   IMPORTING

     RETURN                        = ls_return

   TABLES

     DOCUMENTSTRUCTURE = lt_docstr.

bapi commit.

Regards

Sanja