The booking class is eligible for an upgrade to Premium Economy ( if there is award availability) however , as per
https://www.aa.com/i18n/aadvantage-p...r-airlines.jsp
Reservations booked through a source other than American Airlines must include at least one flight with an American Airlines flight number in order to be eligible (includes codeshare flights operated by British Airways or Iberia but booked as an American Airlines flight number.)
Do you have any flight in your itinerary that is booked as an AA flight number? If so, then you meet the eligibility requirements , otherwise you will have to settle for travel in economy ( or pay fare difference )