It may be that your local dealer hasn't seen this issue, but VW sure knows about it!
Have your dealer check with VW techs, and they will advise how to troubleshoot the issue. From my experience, and others, it seems that a "lube and adjust" is the first fix that should be tried. If that doesn't work, it's probably the frame alignment, and that will entail removing and replacing the entire roof assembly.
Note that in order to get to the sunroof frame, a good deal of the interior must be disassembled. It's a big job. If your dealer has to do it, carefully inspect the completed job, and check every interior panel, and the seals around all the doors. Also check that all switches and lights are working properly. Look for any misaligned panels or gaps. Also carefully check the sunroof assembly from the outside, especially all the seals and gaskets. Everything should be aligned, and the roof should fit tightly when closed. Finally, inspect the paint all around the sunroof for any scratches or nicks, as some work is done from above.
My dealer did a very good job, but it's not a repair without some risk if your dealer isn't careful.