Business Intelligence report - using POSOisclosed filter in report and data not correct when running report

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I have created a excel pivot report using the BI report manager and connector.  I have several fields used to construct an open order report by ship date I them use Vlookup to link to anoither table from our MRP system to show On Hand FG inv and current WIP.

The problem I have is the POSOisClosed filter. I only want to see open sales orders but I have a sales order that is closed but the order shows as open on the report. 

Can anyone explain what I may be doing wrong? 

Thank in advance.

Craig.