Lufthansa complaint: Customer Neglect

I booked a return frlight from Heathrow to Munich (Weds 13th Jul to Sun 17th) using SkyScanner. When I checked my Lufthansa app, my return flight was ed as Dresden. As this was not correct I went to the Lufthana Customer Service desk on Sun to ask why I was flying to Dresden. The Luftansa rep ed that this was an error and my flight had been cancelled and should have been re-booked. Although nobody had informed me and my flight was not re-booked. She was able to get me on another flight to Heathrow the next day at 17.30. So we (myself and my son) had to spend a night at the Hilton at the airport (which was expensive). When I arrived back at Heathrow I was a day late and the car park charged me £250 extra. All together I am out of pocket over £600 because nobody booked me on another flight once the first one was cancelled. Both Skyscanner and Lufthansa and pointing the finger and blaming each other.