ptreq_attabsdata - ptreq_header - ptreq_items join is not getting data

Hi masters,

I'm trying to join three tables and call the report with personal number or begin/end date.

However gt_outtab is filling with nothing.

Can someone help me to make the join work ?

Thanks.

    SELECT a~request_id a~status a~mod_user

      c~pernr c~subty c~begda c~endda

    INTO CORRESPONDING FIELDS OF TABLE gt_outtab

    FROM ptreq_header AS a INNER JOIN

    ptreq_items AS b ON a~item_list_id = b~item_list_id

     INNER JOIN ptreq_attabsdata AS c ON b~item_ins = c~item_id

    WHERE c~pernr IN pernr AND

        c~begda IN begda AND

        c~endda IN endda.