The likely causes of this issue are:
The PIR you are trying to approve has not yet been matched.
The PIR you are trying to approve has been rejected.
If the PIR has not yet been matched:
Log in to Dimensions.
Browse to Creditors, Match, Match Order
Find the invoice using the search filters
Double-click the invoice.
Match it accordingly (seek advice from a user who usually does this process if you are unsure)
Click **Save**.
Choose an approver to send the PIR to
If the PIR you are trying to approve has been rejected:
Log in to Dimensions.
Browse to Creditors, Match, Match Order
Select **Include Match Orders**, then find the PIR invoice using the search filters.
Double-click the invoice.
Unmatch it by setting all PO lines in the top half of the screen to "NO" - double click to change this
Click **Save**.
Browse to Creditors, Amend Entry
Find the invoice using the search filters
Double-click the invoice.
Click **Save**.
Browse to Creditors, Match, Match Order
Find the invoice using the search filters
Double-click the invoice.
Match it accordingly (seek advice from a user who usually does this process if you are unsure)
Click **Save**.
Choose an approver to send the PIR to
The Invoice should now be able to be approved by whoever it was sent to and the error will no longer appear.
If the Invoice is definitely matched and not rejected, contact support.