Hi Ellen,

In Illinois, the assignment will generally reference the recorded document number of the mortgage/deed of trust securing the assigned note.  It may not be referenced if the assignment was recorded concurrently with the security instrument.  If the assignment is only assigning one note, I would check the documents recorded immediately before and after the assignment to see if the document is misposted or defective in a way that it would not be posted properly.

If the security instrument is not found, I would include a note to that effect with the assignment on the report.  The lender will have a credit report and should be able to determine whether the note exhists. 

Hope it helps!