Raycast doesn't find mesh

I have an automated layout generator, made from hexagon meshes. I want to be able to click on it.

I want to do this with a raycast, but unfortunately, the raycast can't find any colliders. The different meshes have a mesh collider.

 void Update()
     {
         if (Input.GetMouseButtonDown(0))
         {
             Debug.Log("Click!");
 
             Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
             RaycastHit2D hit = Physics2D.Raycast(ray.origin, ray.direction); 
             if(hit.collider != null)
             {
                 Debug.Log("Yeah");
             }
         }
     }

There are lot's of questions and answers about this topic , but none of these actually helped. I couldn't find a question specific for meshes.