WMS: How to use flexfield in master item on putaway rule ?

Hi,

   I create putaway rule as below but it's not work.

  

    Object                                Parameter                 Operator      Object    Parameter

    Destination Subinventory     Subinventory Name         =            item       ItemSubInv   --> this one is flexfield's parameter in master item and value = subinventory name (e.g. FREEZE)

    Is this correct ? do I need to add other conditions ?

     Please help advise.

Thanks