Oil drain plug dripping!

My 2002 Jetta is now 2 weeks old since I bought it.Problem with oil dripping from the oil drain plug.First I cleaned the oil pan, maybe oil splashed around when the dearler did the oil change.Nope that wasn't it,so I tighten the bolt,no help.Took it back to Autobarn in Mountprospect Il. I have a 2year warrn. on the car.Took the car and lifted it up and told me that I put in a aftermarket drain plug.Yes they told me that this car left there lot with a V.W. oil drain plug and that I change it and crossthreaded the screw.That is why it is dripping they told me.Autobarn did not want to fix it under the warranty.Not to happy me did not stop there and argued with the salemanager,there mechanic has made a mistake and Autobarn wanted to cover it up and wanted to blame me.Autobarn was shoving down my throat all about there Car Certification that they cover the hole car with the warrn. and check the entire car.I do still have a problem with the bright lights turning on and to stay on.I do like the car,don't get me wrong there,just the service dept. personnel I had do deal with. bobinkski.

They obviously knew the car had an aftermarket drain plug in it and didnt want to spend the 350.00 to have a new oil pan put on. If its certified than it should have been fixed. Looks like they want your money. And lets see... VW oil filter and aftermarket drain plug..... right doesnt make sense. Maybe a jiffy lube filter and aftermarket plug..