Huge area with strange invisible walls

What this problem is related to? (e.g. Broken model or texture / Incorrectly placed model / Particle Effect / Animation / Collision problem / etc. ):

Location/Coordinates (/pos, if relevant): There is that corridor with strangely put invisible walls through its area. Not only the walls are weird, but they also work like an actual wall and prevent shooting and casting (I think) through it. There are walls sometimes on spots where they should not be.

Describe the problem:

List the steps that occurred before the problem appeared (if relevant):

Can you reproduce the problem? (if relevant):

Screenshots/Videos (if available):