I'm trying to book an award ticket from CDG-SAW (Istanbul) on TK with UA miles. There is award space available, however united.com doesn't seem to recognise SAW as a valid airport. If I search for flights into IST I can see the flights that would land at SAW as opposed to the main international airport (IST), but then when I click through to book I get an error. A call to United reservations didn't sort anything out. Any suggestions??