If it is every time, including when firing, you have a broken, missing, or nonfunctional extractor. The simplest problem would be a piece of junk under the extractor preventing it from engaging the case rim. It is also possible that you are riding the slide slowly home, causing the extractor to not engage the case rim. Grab the grip in one hand, the slide in the other, push the grip forward, yank the slide back, and let it fly into battery. If this doesn't work, you need the explore the issues I described.

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Wisdom comes thru fear . . .