I am trying to make an award booking using the multi-city function on Delta.com.

I plug in my itinerary, pick out my flights for the 4 segments and then at the end I get an error message saying "One of the flights you selected just sold out. Please try searching again". I get this all the time and the DL CS folks aren't any more helpful.

Am I the only one getting this issue or does DL really not want me redeeming my miles?