Issue With Approval Processing Line?

I am trying to write a report that lists invoices that are awaiting approval in NaV. I am able to get a list of open invoices, and most of the time the report correctly lists the people that still need to approve.

Here's a formula I've been using to pull blank approvals:

NL("First","Approval Processing Line","Action ID","Document No.","@@"&$J10,"Sequence","0","Decision","''","Business Rule Code","4*","Internal Control No.","*")

Action ID is the user name. Document no. references the invoice number. Other formulas pull sequence 1 and 2, depending on approval rules. I want to pull blank decisions, so used two apostrophes (single quotes) surrounded by quotation marks. Business code rule is specific to the department I'm writing the report for.

It works about 90% of the time. Other times, user names will appear even though they already approved. Or a user name won't appear that should, because he hasn't approved yet.

Any suggestions?