My cars are crashing into randomly appearing invisible walls or something

When I start the game (a racing game I made using Chaos Vehicle), randomly invisible walls appear on the map, and after a while, they disappear. I’ve checked all the objects, but I can’t seem to find what’s causing it. How can I solve this ?

video: https://www.youtube.com/watch?v=T4zpbsFDvOQ

Turn on viewing for collission. See it there is indeed some weird collision from for eg invisible landscape or such.

I did but seems nothing

Is this road done from spline? maybe this happens where segments overlap.

Not from unreal experience, however:
I played Satisfactory, that is made on unreal, and there it is quite possible to mess splines roads or train lines. Ie. you mistakely swap (rotate 180 deg) one of segments, so edge between two has hidden degenerated (0 length and 180deg rotation) loop segment.

press f8 (to go back to editor mode while in game) and view collisions, this should let you identify what is causing it - make sure that the mesh has (e.g. if you had made a simple collision, use simple collision as complex checked)