Spring joint collision problems

Hello, i hope i’m in the right forum.

My situation is shown in the picture.

both rigidbodies have 1 box collider,
the rigidpody of the plate has fixed rotation and fixed X/Z positon.
(not kinematic or anything)

Does somebody know what to do :< ?

thanks,
david

problem not solved yet : <

3 years later, I am having the same problem. Anyone knows how to do this?