No collisions for the cube attached to the character in TPC project

A very confusing question is, when I add a cube under the CapsuleComponent(no matter under which component) and attach this cube to the component in Blueprint (here I attach it to the mesh component), the cube can’t perform collision with walls or boxes even if I enable all collision or physics setting. This is strange!

My requirement is: adding a cube in front of the character and keeping relative static with the character. When the character walks to the wall, if the cube touches the wall, the character no longer walking forward. Is there any solutions to solve it?

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