While my cube is moving my RollerBall doesn't collide with the cube and falls, but when is not moving it colides and doesn't fall.

How can i solve my collision problem. i would like my RollerBall not to fall although the cube is moving. Here is my rotating script (C#)

 using UnityEngine;
 using System.Collections;
 
 public class rotate : MonoBehaviour {
         public float myRotationSpeed = 100.0f;
 
         public bool isRotateX = false;
         public bool isRotateY = false;
         public bool isRotateZ = false;
 
         // CHANGE TO ROTATE IN OPPOSITE DIRECTION
         private bool positiveRotation = false;
 
         private int posOrNeg = 1;
 
         // Use this for initialization
         void Start ()
         {
             GetComponent<Collider>().isTrigger = true;
             if(positiveRotation == false)
             {
                 posOrNeg = -1;
             }
         }
 
         // Update is called once per frame
         void FixedUpdate ()
         {
             //  Toggles X Rotation
             if(isRotateX)
             {
                 transform.Rotate(myRotationSpeed * Time.deltaTime * posOrNeg, 0, 0);//rotates coin on X axis
                 //Debug.Log("You are rotating on the X axis");    
             }
             //  Toggles Y Rotation
             if(isRotateY)
             {
                 transform.Rotate(0, myRotationSpeed * Time.deltaTime * posOrNeg, 0);//rotates coin on Y axis
                 //Debug.Log("You are rotating on the Y axis");
             }
             //  Toggles Z Rotation
             if(isRotateZ)
             {
                 transform.Rotate(0, 0, myRotationSpeed * Time.deltaTime * posOrNeg);//rotates coin on Z axis
                 //Debug.Log("You are rotating on the Z axis");
             }
 
 }
 }