void Move() {
//same thing was happening when i commented out this check
 if (i.horizontal != 0f && i.vertical != 0f)
                agent.isStopped = true;

            float _speed = walkSpeed;

            if (controller.isGrounded)
            {
                moveDirection = new Vector3(i.horizontal, 0.0f, i.vertical);
                moveDirection *= _speed;
            }

            if (!controller.isGrounded)
                moveDirection.y -= gravity * Time.deltaTime;

            controller.Move(moveDirection * Time.deltaTime);
}

  public void MoveWithmouse(Vector3 pos)
        {
            if (controller.isGrounded)
            {
                agent.SetDestination(pos);
            }
        }