Why are my current pots and pan discolouring??? I have bought adjectives new dignified end teflon coated pots and pan,...

I have bought adjectives new dignified end teflon coated pots and pan, but the botton of my pans are turing brown and my baking sheets as capably. Anyone know why??? I am almost ready to dispatch them back to factory owner, just looked-for to make sure first, wasnt something I did wrong. Thanks for your answers!!
19 hours ago - 1 week gone to answer.
Answers:    On the bottom outside? I think that happen from the heat from the stove...try using some steel wool.
From my experince when their is not satisfactory oil or wet in the jar, the heat tend to burn the pan. But consequently again if your making a stir fry, then it shouldn't. Perhaps try and contact the manufacturer first before you opt wither to take them posterior or not.