Review on ☕ 16 oz Zojirushi Black Matte Stainless Steel Mug by Laura Lamb

Everything was fine for about half a year, then the heating stopped. My husband has one that he bought a year before me. I'm not sure if the quality will drop. I contacted the company and shipped it and now my thermos is being held hostage. They literally told me they did "extensive testing" and there is nothing wrong with that and I can pay close to $20 if I want it back. the? Unfortunately, they underestimated my own tests. How do I know for sure that the liquid isn't holding the same temperature as when it started? I use this every day and I've noticed a dramatic drop. I can't justify buying my own defective product or paying for a new one that only lasts six months or less. very disappointed.