How to move an object with its parent?

Hello everybody, My question is how to make my 3rd person controller as an object's child. In my project, I have a 3rd person controller and a moving platform. When I jump on the platform, I want to make my player move wherever the platforms move. So I decided to make my player child of platform so they can move together. I tried this code but it didn't work.

 void OnTriggerEnter(Collider other) {
         if(other.tag == "platform")
         {
             Debug.Log(transform.parent);
             transform.parent=other.transform;
             Debug.Log(transform.parent);
         }    
     }

When I jump on the platform, I saw on my console that my parent object changes to my platform but they don't move together. Any ideas to solve this problem?