If you're having trouble getting 12 rounds into your Bodyguard 2.0's magazine, even with a magazine loader like the Uplula, fret not. The springs can be stiff as hell from the factory.
Take off the base plate, remove the pinky-support extension, and jiggle the spring and follower out past the magazine's rails. Awkwardly compress the spring in your hands a few times to break it in. You don't need to get it to fully collapse within itself, but give it the beans.
Reverse the procedure: jiggle the spring and follower back in, put the extension on, and slide on the base plate until it clicks. With some effort, you should now be able to cram 12 rounds into it. Once you've done it once, it should become easier from here on out!
Finally, jam the magazine up into the gun a few times with the slide in its normal forward position. This will compress the stack of rounds even more, albeit only slightly, and it's the final piece of this silly puzzle.