Indiana, I haven't been on for a while or I would have responded sooner. My LC9S Pro locked back 3 to 4 times per magazine when I first got it. All the above suggestions are good, but in my case I was very careful to keep my fingers off the slide lock lever. Also, I was not limp-wristing.
I called Ruger and explained the problem, they sent me a return label right away. When I got the gun back, in about a week, they had replaced the slide assembly and the slide lock lever spring.
Since then, it's been working perfectly. I hope yours is now working whatever the problem. These are very nice pistols.