Tween stops prismatic constraint working correctly

You can write your topic however you want, but you need to answer these questions:

  1. What do you want to achieve? Keep it simple and clear!
    I have a platform that moves horizontally using a prismatic constraint. This works correctly by itself. I have another “box” part that I welded to the platform, and the platform and box move together no problem.

  2. What is the issue? Include screenshots / videos if possible!
    The problem occurs only when I try to create a Tween on the box. The platform stops moving, however the box tweens and is moved by the prismatic constraint.

  3. What solutions have you tried so far?
    I have tried making the box massless with no effect. I have tried using task.spawn to trigger the tween with no difference. The box and the platform are not anchored.

I really just do not understand why the box is moving as the attachment is in the platform, and i’d like to have the tween effect on all boxes whether still or moving.