Most likely because the number of available Ocean View rooms that can accommodate 3 people dropped below a certain number (likely after your first 2 rooms went into the system, assuming they aren't each being occupied by 3 people). Cruise lines like to cruise with as close to maximum capacity as possible so they will try to fill cabins with their maximum occupancy. Typically the further out from your departure date it is, they try to keep as many cabin/occupancy options open as possible for new bookings coming in. Since there are only going to be 2 people in your cabin they most likely gave you the closest Ocean View room to the others that accommodates only 2 people (7325 can accommodate 3).
You can always try switching rooms closer to your cruise date.