AI LOS Stuck

Hi,

I used this tutorial to create the AI character :
[Creating AI in UE4 Part 1 - AI Components - YouTube][1]

Actually My “AI character”" (that is a big word for what it is at the moment ^^) behave good but I have
a serious problem which is when the AI move to the player the other AI behind get stuck sometimes
so I assume that the LOS is break or there is an obstacle. I’ve tried to change the collisions setting of the AI character (Traces Responses) but I have the same problem.
And Also the AI get stuck to each other but this is another problem (ROVavoidance).

If anyone has any idea or if you guys could help me I would appreciate it.

Thanks