Originally Posted by
sbm12
Seat map is not the same as booked. It is entirely possible (and quite likely in this case) that the seat is sold but not assigned.
Yep as sbm12 pointed out. What normally happens is that people in premium classes don't normally have seats assigned for their flights. Even though a seat has been booked. This is most likely why only 1 seat is showing but two seats are unassigned.