Switching from SimpleMove to Move

Did you check if the character is grounded ?
look this sample code below

     public float jumpSpeed_ = 8.0F;
     public float gravity_ = 20.0F;
     public float acceleration_ = 10.0F;
     public float maxSpeed_ = 100.0F;
     public float curSpeed_ = 10.0F;
     private Vector3 moveDirection = Vector3.zero;
     public CharacterController controller_;
     
     // Update is called once per frame
     void Update () {
         if(controller_.isGrounded)
         {
             // We are grounded, so recalculate
             // move direction directly from axes
             curSpeed_ += acceleration_;
             
             if(curSpeed_ > maxSpeed_)
                 curSpeed_ = maxSpeed_;
             
             moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
             moveDirection = transform.TransformDirection(moveDirection);
             moveDirection *= curSpeed_;
             
             if(Input.GetButton ("Jump"))
             {
                 moveDirection.y = jumpSpeed_;
             }
         }
         
         // Apply gravity_
         moveDirection.y -= gravity_ * Time.deltaTime;
         
         // $$anonymous$$ove the controller_
         controller_.$$anonymous$$ove(moveDirection * Time.deltaTime);
     }