MIRO Invoice Posting Line Item Not Available

Dear Gurus,

I am trying to post a PO Invoice. There are 10 line items in the PO but two of them does not appear in the list of line items when trying to post the invoice by entering the PO number in MIRO.

There is no prior invoice exist in the PO so all 10 line items are open and should show up while processing the invoice.

I checked those 2 line items which do not appear and nothing seems to be unusual about them. Do you know what could be the reasons?