Error while trying to Post Pending Invoice

Hi All,

I am trying to post an invoice. Don't know why it is throwing an error all of sudden.

The error is "Access Key is Not Valid".

As per the stack trace when I debugged, it is leading to the table (VendInvoiceInfoTable_W) and method (validateWrite())

Please find the below screenshot.  In the Image, I have marked out the lines from where the error is coming from. I am unable to understand what is going wrong. I have also checked in the Table (VendInvoiceInfoTable_W) the AccessKey_BR field is blank for that particular PO.

Please help me to understand the error and to clear it.

Regards,

Ram