I have a brand new X1 Carbon. Just had the same issue so came here. I’ve had the printer set up for 2 days. Printed first 3 things with PLA. All worked perfect. Printed a small cube with ASA, was perfect also. Started a bit larger ASA job and it did this about 75% (1.5hrs) of the way through. After reading everything here I’m going to assume it’s the magnets giving out from the high heat. Going to try the methods suggested above to try and makeshift tie it on. But just wanted to add to the list so they might get moving on a proper solution.