You got a good price on it. Mine was $370.

On Sunday I took mine out for the first time and went through 500-700 rounds trouble free. First I went through two mags of mini mags, blazer bulk, federal bulk, and american eagle. After that I finished the 375rd box of federal and got about half way through the box of Blazer. The only problem I had was when forcefully inserting the magazine during slide lock the top round would pop out of the feed ramps a bit which stove piped when I released the slide.

Hopefully you can figure out why yours isn't working. Before shooting mine all I did was whipe off the factory oil/grease and put a few drops of Hoppes gun oil on it. I also dry fired it ~100 times which smoothed out the trigger quite a bit.