How can I get rid of "creases" between collision boxes on adjacent meshes?

Hello everyone, I hope you are doing well.

I have created a few minigolf levels. The gameplay is just like you’d expect - the player pushes a ball around and tries to get it into a hole. To create the level, I used brushes that I then turned into static meshes with added collision boxes. However, there is a small issue - when the ball rolls from one mesh to another, it behaves as if it hit a bump and jumps up in the air a little. This happens in spite of the fact that the meshes seem to be leveled perfectly. It’s rather annoying as the player will expect the ball to roll smoothly but I have no idea what could be the cause of something like this. Any help would be much appreciated.

Can you show some pics?

Sure, here they are. In the first two pics you can see how the collisions are structured on two platforms that I use. Note that the boxes at the bottom have the same z positions and height, as shown in the editor. In the last pic, you can see how they are positioned in the level. In the editor, you can see that they have the same z and y coordinates.