For the record, I had the same problem the same day. Also booked award tickets, got the booking confirmation with booking code, but the miles/cc charges were never deducted. I could see my reservation on the KLM website in my bookings, could select seats, but the tickets never got issued.
A day later the reservation disappeared from the My Bookings list and the booking code resulted in an invalid itinerary.

Booking the same on the AF website worked without problem.

Now, I want to select the seats and the website says "We are sorry, but it is temporarily not possible to show the seat map. Please try again later!"
Seems like there is something going wrong at KLM!