Front Seat Belt Buckle Assembly problems of the 2002 Jeep Wrangler

I own a 2002 Jeep liberty and noticed that the drivers seat belt button sticks. . Usually in colder months and it's difficult to fasten the belt (as it will not go into the slot). Not sure if this is covered as I believe its defective. Doesn't' do in summer, just winter. My warranty is expired, I have approx 45k miles on the Jeep. How do I proceed? do I just have dealer fix & should it be free of charge since there are other complaints from folks who own the same model/year?.