This has happened to me twice in just under two years, the best way around it is to buy a new handle £6 and the mech that it clips onto £4 (bought from main vw dealer) and just replace it, it is a bit of a pain and slightly fiddly but i think the cause is the cable itself may have seized up a bit causing the teeth on the handle and mech to give way. According to my uncle (porsche,ferrari, lamborghini Specialist) it wouldnt be a hard job running a new cable, hope this helps