Mossberg fan

We took my bow to a proshop and the guy said he knew what was wrong. He said the cable gaurd bar was at the wrong angle. So he put a new one on and put a different stabilizer on to help reduce vibration. We'll see if this works. But I still have a problem. At ten yards, I was stacking arrows on top of each other, but when I moved back to twenty, they were going all over the place. What can I do to help with this?

SW Iowa Hunter

Maybe I have missed a previous post, but I have had the same problem before when my arrows were not splined properly for my set up.