Maybe a quick cable adjustment is all you need. The control when pulled back, contacts a stop switch. You will want to see that it is being activated. A wire leaves that switch and goes to the ignition coil under the shroud. Basically it supplies a ground to the coil to stop the engine.

If you can't figure it out you can shut the gas off. You should be doing that anyway after you are thru using it.

"a little over a year old" You would think less than two years old it may be under warranty?

I got one that wont' die also as in give up the ghost. It's been pulled out of the trash twice. Freebee on side of the road, ran it for 4 years, gave it to my son, he ran it for 3 years, discarded in the trash pile. I again drug it home, cleaned out the gas tank and carb. decarbonized the head, changed the oil, and Bam fired right up. Most would call it cheap crappie craftsman with TEC flat head engine. But I still starts on the second or third pull and is at least 15 years old.