This complaint concerns our miles and more award tickets reservation UD9GLT (Olesen Niels and Maryam): 1. This booking was made and confirmed in May 2. On June 2, we received an email informing us that the return flight on July 26th was re-booked on a later flight leaving at 18:00 (LX4705) and if ok for us, we just needed to confirm via the email option, which we did 3. We left as planned on July 18th and arrived in CPH from ZRH 4. On Sunday July 25, I went online to check-in for the return flight, but our booking had disappeared. BUT WE HAD NEVER BEEN INFORMED! 5. I spent 35 minutes on the phone with your customer service in Germany who contacted SAS and confirmed to me that she was able to convince SAS to re-book us on the flight LX4705. We received a confirmation email later that evening from Lufthansa 6. By chance, I re-checked on Monday morning and to my surprise the flight booking had disappeared again WITHOUT INFORMING US!!! 7. Another 38 minute call with your customer service who re-confirmed that she was able to re-book us on that flight and that we would receive a confirmation email shortly. 2 hours later, still no email confirmation so called again and the consultant checked and said all was ok, it was just taking some time, but we could go to the airport no problem 8. Finally I called again later at 13:09, worried about not getting any email confirmation. The Senior consultant on that call told me there was no way we could get booked on that SAS flight due to an issue with the reservation class!!! Different information than all the previous consultants I talked with. She offered to re-book us on a Swiss flight leaving the next day, which we agreed to. In conclusion, we are very upset by the back and forth with conflicting information and if I had not checked, we would have gone to the airport on the 26th (long drive) and would not have been able to fly!!! Also very upset that between June 2 and July 25th, we never received any information from Miles and More that our return flight had been cancelled!!! I wasted a very long time and a lot of frustration due to this appalling service from Miles and More. I look forward to your explanations and a compensation for all the time wasted and additional costs incurred (prolongation of car rental by one day and over one hour long distance calls)