Additional duplicate invoice hold question

Summary:

We have the Additional Duplicate Invoice check feature enabled however, we have noticed that some invoices with the same supplier, invoice type, amount, currency, and date are not triggering a duplicate invoice hold. They are all standard invoice type. Is there another parameter that is considered to determine if the duplicate invoice hold applies?

Content (please ensure you mask any confidential information):
We did notice that when the invoices met all the parameters of the additional duplicate invoice check but had a different source the hold did not trigger. Is the invoice source taken into consideration?

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