Flights missing when making reservations
 

This has happened before, but seems to be worse the last day or so. When searching for flights, sometimes about half of the flights for a leg are missing. It's not that they are sold out. Have been monitoring ATL/AUS, and most of the time, only three flights show for the return.

Checking for a friend on a plane that leaves ATL to MSP today in about 2 hrs, the flight does not show up. He's monitoring the seat next to him.

Anyone else notice this? How can this happen?

First of all, seat maps are not the most accurate way to judge availability. Expert Flyer is very useful when it comes to determining if a flight has seats.

Given conditions in ATL today, many flights are likely full or overbooked. No longer being for sale on DL.com is one indicator the flight is oversold. Empty seats on the seat map do not mean there's availability, as some pax get seat request cards and their seat at the gate.

Searching by price will limit the options shown on the Delta.com search. If you search by schedule the results will be more complete.

Generally I use ITA or Kayak to find what I want then search for those specific flights on Delta.com using the multi-city search.

This. Always search by schedule if you want to see all options. Searching by price does goofy things.

Once a flight is sold out, it appears that one can look at the seat map only by logging in and clicking in the seat number, which will usually bring up something like a statement that you cannot change the seat and do you want to continue to just lok at it.

Remember to look at later pages or click "show all" to see flights, which are not necessarily listed inane logicl order. Non stops that are expensive can appear in the middle of a long list of crazy connections.