Problem to disable collision with canvas

Hello

I am taking the first steps in unity 5 with the development of a small 2D game of cars seen from top down.

I am using 2 Canvas to render 2 par of sprites that are roads. I have 2 types of roads with 2 sprites for each to make the loop and I want the roads to be rendered by each X score points.

The solution I m using is enable /disable cameras to make the transition between the loops, but I can t disable de collider2D component from first road.

There is a better way to make the transitions ? and how can I disable the collider when I go to the 2º loop road B?

Here is some of the c# code of my script:

         if (scoreNum >=10){
     
     camera.enabled = false;
     camera2.enabled = true;
 
 Physics2D.IgnoreCollision(player.GetComponentInChildren(), roadB1.GetComponentInChildren()); // Don t work!!
 
 Physics2D.IgnoreCollision(player.GetComponentInChildren(), roadB2.GetComponentInChildren()); // Don t work!!
     
     roadA1.rectTransform.Translate(moveDir * (velocity *20) * Time.deltaTime);
     roadA2.rectTransform.Translate(moveDir * (velocity *20) * Time.deltaTime);
         
     if(roadA1.rectTransform.anchoredPosition.y < -520){        
         roadA1.rectTransform.anchoredPosition = new Vector3(roadA1.rectTransform.anchoredPosition.x, roadA2.rectTransform.anchoredPosition.y + 520, 0);
     }
                     
     if(roadA2.rectTransform.anchoredPosition.y < -520){            
     roadA2.rectTransform.anchoredPosition = new Vector3(roadA2.rectTransform.anchoredPosition.x, roadA1.rectTransform.anchoredPosition.y + 520, 0);
     }
                     
     }
         
     else {
     roadB1.rectTransform.Translate(moveDir * (velocity *20) * Time.deltaTime);
     roadB2.rectTransform.Translate(moveDir * (velocity *20) * Time.deltaTime);
                         
     if(roadB1.rectTransform.anchoredPosition.y < -520){        
     roadB1.rectTransform.anchoredPosition = new Vector3(roadB1.rectTransform.anchoredPosition.x, roadB2.rectTransform.anchoredPosition.y + 520, 0);
                                 
     if(roadB2.rectTransform.anchoredPosition.y < -520){            
     roadB2.rectTransform.anchoredPosition = new Vector3(roadB2.rectTransform.anchoredPosition.x, roadB1.rectTransform.anchoredPosition.y + 520, 0);
     }
                         
     }