I bought a ticket from Emirates website for CMB to DXB, DXB to GRU, GRU to PTY. This is all a single ticket issued by Emirates. In this ticket, GRU to PTY is operated by COPA airlines (CM702 flight number).
After the order, I selected my seats for CMB to DXB flight and DXB to GRU flight.
How do I select the seats for GRU to PTY? The Emirates website is saying seat selection isn't available for flights operated by other carries. I took the ticket number and plugged it into COPA airlines website and it's saying that seat selection is not available for this passenger.