Navmesh agents not colliding with non trigger colliders?

Basically I have police cars following the player on navmesh tiles. The police car prefab has a non trigger collider that should collide with other police cars/buildings around it but they're not working. The police cars can go through each other and can go through the buildings that are at the edges of the navmesh tiles. There are two box colliders on the car prefab, one that's slightly bigger than the car that triggers the death of the player when it touches them and one that's the size of the car that is supposed to collide with the environment but it's acting like 'is trigger' is ticked. Is there a way to fix it so the cars can't go through each other/buildings?