It's a Samsung, 2 elements in 2 years wouldn't surprise me at all. Sorry but their elements just suck. I do one a day on average, I doubt you'll find anyone who would warranty that part for long. It just has a long, sad history of failure.

It'll be your element itself or the thermal cutoff probably.

Whole duct: http://www.appliancepartspros.c...97-14486a-ap4342351.html
On that pic the cutoff is the smaller component closer to the round end of the duct, about 1/2 way down lengthwise.

If you have a multimeter you can test either part easily. The simplest way is to notice that power supply to that element comes from 2 sources and comes from under outlet duct. I think they are blue and red at that point? One wire (blue?) goes to thermal cut off, loops to thermostat and then to one side of the element. The other (red) goes directly to the element. Each supplies 120V AC to the element, making 240V at the element. I may be wrong on colors; I know there's a black loop in there somewhere too, between cutoff and thermostat I think.

You are looking for little to no resistance along the chain of thermostats leading from the thermal cutoff to the element, if your meter says OL or INF it is open. You can disconnect the wires and test each component in isolation, the element itself will have resistance, the other 2 should not.

If you have the old part you may still have a good thermal cutoff on it, depending on if it or the element opened. But I'd put odds on the actual element being bad.

There are a few more exotic causes that we'll leave alone for now.

Accessing the interior is easy. You can probably find a youtube vid on it, but post back if you want instructions.

With the high rate of failure it makes sense that somebody would attempt to make a non OEM version.
If the home warranty thing doesn't cover it I would still open it up and verify that the element or the cutoff has failed. There were a batch of their motors that had failed centrifugal switches and were not sending power over to the element.
So if you end up doing it yourself verify those thermostats or element as the issue.

What's sad is that it's not just Samsung products but across the industry quality has decreased dramatically in the past decade. I repair all brands and there's no one brand I would recommend for all appliances.