I believe I have found the cause of my problem. When I insert the magazine to release the slide forward, the hold open device is not fully depressed as it should be. I either have a worn magazine or the magazine I have is not the proper one for my pistol. In either case I see that I must now find a replacement magazine for a Mauser 1914 Pistol. I suppose this will be as easy as finding chickens with teeth. I thank all of you that responded, you helped me identify my problem and now I can move on to the more difficult task of correcting it by finding a replacement magazine. Again, thank you.