I hope S&W will fix it for you. Technically, their warranty only covers the original owner, but most of the time they don't ask. I've read of a few instances when they would only work on a second hand gun for a fee, but that hasn't happened often. Like I said, most of the time they don't even ask. That's not information you should volunteer, BTW.

Sorry, I can't offer any suggestions other than don't do any modifications or attempted repairs yourself until you talk to S&W. They might not work on it if you've tried to polish the feed ramp, etc.