Shark, first thought is a bad mag. Do you have more than one? if so then the question is does it do that with the other(s)? If it is a bad mag contact Bersa, they will send another out to FREE ifitis defective. Also what ammo are you using? I have heard of some having this issue with the "cheap" ammo.
I aven't had any issues with my 380, and my confidence in it is very high if I need it.