Collision & trace are not responding during a game

Hello,

We have more informations about this bug:

-Collisions seems to disappear only on serverside (but also during a solo game) client side has collision
-Appear only on a specific area
-The bug affect only blueprints

Here is a little video (clientside) with show collision ON, collision seems to be here…


Here is my stat game (on serverside):

Anyone with an idea please?