Swipe menu, problem with the first instantiated gameobject

Question

I am making a map selector for one of my projects, and I have a strange problem with the first instantiated image. Here are two pictures so you can understand better:

So it's a list of prefabs that are generated in the start function, the prefab that is in the center of the camera gets bigger to be highlighted, and the others get smaller. Except that it works on all the images, except the one on the far left.

Also, I have the following error in the console but no precision on the line in question.