Vehicle starting then stalling

So I recently had work done on my car, replacing the AC compressor, the serpentine belt, and the tensioner assembly, and Last night I left my car in park idling as I went inside to grab something. It took me a few minutes but when I came back the car was not running. I originally just thought "weird" and started it back up. It started just fine, all the electronics are working and I had just filled the tank earlier that day. It ran for about 5-6 seconds before stalling again. Recreated this effect at least 3 more times before giving up for the moment.