Many of you have trouble with your hi-point magazines. Aside from leaving them loaded for a while to let the spring break in , adjusting the magazine feed lips can be done in order to better the function of the magazine. This can be done by bending either the forward or rear feed lips in or out as needed, you can do this easily with a set of needle nosed pliars. Hi-point tech support has also recomended that this be done if needed.
Here are a couple of commenly used diagrams for the c9 that can help give you an idea on how your feed lips should look when adjusting.