hello, a few years ago my dad bought my mom a walther ppk. im not familiar with handguns at all and I tried shooting it a few weeks back and it seems that if I rack the slide it shoots the first shot but will not shoot again. its supposed to be a semiautomatic, this cant be normal right? I sent it to the factory for repair and they sent it back but it still does the same thing. I havent had a chance to call them yet to ask what they found.