Booked in Premium Economy on ZRH-JNB-ZRH over the xmas/new year.

On the return flight, LX.com doesn't bring up the seat map and ExpertFlyer says "There was an error message from the airline when trying to retrieve this seat map: PRS NOT ALLOWED THIS CLASS OR ZONE "

Does this mean it's oversold? Availability is very low in all classes, but especially F and W: F2 A0 J9 C0 D0 Z0 P0 G4 E0 N0 Y9 B0M0 U0 H0 Q0 V0 W0 S0 T0 L0 K0