I booked a RT ORD-SMF/SFO-ORD on the phone yesterday. One is on an Airbus 319, the other on an Airbus 320. When I asked for an "aisle seat, as far forward as possible," the agent said I could have 6C in both directions. I was surprised, as I have no status on UA.

Today, I went to "My Itineraries" on united.com, and see that there is no seat assigned to my reservation. I don't want to make waves and potentially lose such good seats if I have them, but I also don't want to show up at the airport with no reserved seat at all, which is usually a ticket to a middle seat towards the back.

Any advice?