Store Sales Person Id and Sales Territory Id on invoice line

I'm trying to store a sales person id and sales territory id on my invoice lines but it's not storing anything. The IDs I'm passing in the xml do exist in GP, this is my xml for a single invoice line:

<taSopLineIvcInsert> <SOPTYPE>3</SOPTYPE> <CUSTNMBR>ORG-10250</CUSTNMBR> <DOCDATE>20/11/2013</DOCDATE> <ITEMNMBR>PLACEMENT</ITEMNMBR> <UNITPRCE>103.1</UNITPRCE> <XTNDPRCE>1237.2</XTNDPRCE> <QUANTITY>30</QUANTITY> <MRKDNAMT>61.86</MRKDNAMT> <ITEMDESC> Placement: SER-25747 </ITEMDESC> <NONINVEN>1</NONINVEN> <SALSTERR>TEST</SALSTERR> <SLPRSNID>TEST</SLPRSNID> <IVITMTXB>2</IVITMTXB> <TAXSCHID>SZ</TAXSCHID> <SLSINDX>1000-0000-FPA</SLSINDX> <RTNSINDX>6000-0000-FPA</RTNSINDX> <CURNCYID>GBP</CURNCYID> <UOFM>Each</UOFM> </taSopLineIvcInsert>

Thanks