simple consistent maintenance for future reference, but to solve issue is found simple warm up small amount of cooking oil and I mean warm not hot, then good pair of gloves and pour a little into stuck area leave it a bit to penatrate then it should loosen, the only time I've had this is from early one Alex sent me that I had to make groves in it to stop it slipping as it was totally smooth being early model, but never had it on finished items only the early model, so Alex was there a difference in plastics then, my eyes tell me yes but I only came up with solution idea to stop spinning as it was totally smooth and my grove gave you the idea for your version of grip, but I see plastic look different but couldn't say what only Alex will have the answer, for interested the early model is still in daily use today so it's a product that was built to last.