“The warranty covers if the Contigo 16oz.Autoseal Mug is not longer hermetic sealed? my 16-oz Autoseal is not keeping hot the coffee as it used to do it when I bought it in 7/1/2014. is it a manufacture failure covered in the warranty? Now the complete external MUG gets hot. Should I take it back to the store(bestbuy? where I bought it for a replacement? purchase date 12/6/14 for this Contigo 16Oz. AUTOSEAL West Loop Stainless Travel Mug with OpenAccess Lid Blue WLB100E01 purchase date 7/1/2014 for this Contigo 16Oz. AUTOSEAL Randolph Stainless Travel Mug with Lock Black WLH120A05”