how to transform the position of an object

Question

I am trying to transform the position of an object. I have totally 3 Objects and 2 triggers, objects are 1. Left_Wall, 2. Right_Wall, 3. Obstacles. 1st trigger for transform the position of an objects y = -50, 2nd trigger for transform the position of an objects y = -7. Left wall and Right Wall are placed inside the environment. the environment will instantiate automatically for looping. if the player crossed the first environment previous environment will delete automatically. at that time in second clone environment if the player triggered means it will display a message as

MissingReferenceException: The object of type 'GameObject' has been destroyed but you are still trying to access it. Your script should either check if it is null or you should not destroy the object.

In first Clone environment its working perfectly. second clone environment its not working.

Answer 1

Please please please use Code Blocks to paste your code instead of screenshots.

Now you say that

the environment will instantiate automatically for looping

And your variables sideLft and sideRit are null when you need them. So why not perform the search of the scene just before you do your action? Take your code from Start function and move it in the beginning your OnTriggerEnter. I would provide a code block for you if I could copy some from your question.