The first thing you need to do, is to try and heat up the tip of the pen. The most common problem is that pens tend to get a little cold on the tip, and this prevents the ink from flowing through them very freely.
Now in order to avoid this, you need to try and heat up the tip of the pen. This can be done in a number of ways. However, the most common ways are to either scribble with the pen on a piece of paper, in order to heat it up, or to use a lighter or any flame to heat the tip a little bit.
Fix ink placement
Sometimes, the pen tends to end up with the ink in its tube being misplaced. This caused it to not work properly.
You can fix this by either taking the tube out and blowing on it for a few seconds, or by vigorously shaking the pen, in order to get the ink to flow and reach the tip of the pen. This will make the pen work more effectively and will result in your working with no problems at all.
The last thing that you need to fix or consider fixing is the spring in your pen. This prevents the pen from working properly and is usually the source of the problems when it comes to faulty ball point pens.