I have owned two pendulums so far with mixed experiences. The one was jazz and the second was amethyst. The first simply wouldn't move much and gave me half inaccurate answers. The second is better in terms of motion but I still get 60-70% accurate answers. There are times though where I got the same answer no matter how many times I ask the same question and what my current mood and thoughts--positive or negative. So I'm not sure if I believe the popular notion that "you simply move it subconsciously". I have tested this theory and even tried to swing it in a certain direction and it turned out around in the opposite direction almost immediately.
I also don't suggest asking pendulum for future predictions unless they are about to happen in your very near future e.g if you will get the job following an interview. The pendulum is only for validating certain things in your past, present and near future. It simply can't pinpoint future energies unless they are fixed. For example, let's say you are asking if your ex will contact you--that is wrong. It's better to ask:
-Does POI intent to contact me this month?
or "Am I destined to speak with this person again"?
The more precise and clear you are in your questions, the better.
Also, make sure that your new pendulum is energetically charged and cleansed often so you can get more accurate answers. You still won't get 100% right answers every time but it helps. By charging it I mean placing it mineral salts and then visualizing a white purifying energy surrounding it. Or lightly smudging it using a sage stick.
I also sometimes buy cheap pendulum readings from fellow readers on Etsy to validate the answer. I had questions where both my pendulum and a couple of readers gave the same answer e.g strong YES and so I take that answer as certain and fixed.
If you don't get a clear movement or answer, perhaps you are not meant to know it, your spirit guides are interfering or you aren't perhaps secretly ready to hear it. Just my two cents. Still, I believe it has a mind of its own and so you can't exactly manipulate it towards a certain answer.