PO Custom report with Total Currency Converted Ordered Amount

Summary:

Content (required):

I am trying to write the custom query to get the PO total orderd amount , where I am using the" PO_BIP_HELPER.get_ordered_display (PHA.PO_HEADER_ID,'0','TXN','H',PHA.CURRENCY_CODE)" but When I do the Mutliplication with Currency Rate and When I run the data view I am getting an error saying "ORA-01722: invalid number" ,

Can any one help me

Thanks in Advance

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):

PO_BIP_HELPER.get_ordered_display(PHA.PO_HEADER_ID,'0','TXN','H',PHA.CURRENCY_CODE)*PHA.RATE AS "PO_TOTAL"