Chastity and orgasm denial discussion

Hello, I’ve long had a fascination with chastity and am now nearly succeeding in getting my wife on board. We chose the CB6000 because it offered decent value, received positive feedback online, and appeared quite popular. After putting it on, I realized it would be somewhat uncomfortable, which is acceptable. The problem arises when I get an erection; my penis tends to slide back along the curve a bit before pushing the device forward. Based on what I’ve read, this might not be typical behavior, as I think my penis should press against the top of the cage rather than following that curved path. I’m uncircumcised (though I wonder if that matters). Has anyone else experienced this? Is there a fix?