The shop will charge a minimum of a few hours just diagnosing the problem and if you're lucky they won't replace a bunch of parts because that can get expensive quickly. They will evidently get around to wiping the magnets with a rag and fix your problem. Do not let them grease the jack leg. If you ever decide to read the Power Ger thread (with lots of good information) you will find that the biggest problem with working on the jacks is finding a competent shop. Good luck, I wish we could have saved you a trip to the shop.
Jim with Judy
08 38' Bounder DP
Toads: 08 Jeep Wrangler Sport; 11 Chevy Malibu