Unity android screen resolution

I have made a simple 2D game on the latest unity version in free aspect ratio however whenever I change the screen to portrait or landscape things mess up. Now I have spent the whole day following tutorials and going through every tutorial or answer available but strangely not even one of the code helped. Here is how my screen looks on different resolutions

Right now I’m using this code

using System.Collections;
    using System.Collections.Generic;
    using UnityEngine;

    public class Screeratio : MonoBehaviour {

        // Use this for initialization
        void Start () {

            // set the desired aspect ratio (the values in this example are
            // hard-coded for 16:9, but you could make them into public
            // variables instead so you can set them at design time)
            float targetaspect = 16.0f / 9.0f;

            // determine the game window's current aspect ratio

            float windowaspect = (float)Screen.width / (float)Screen.height;

            // current viewport height should be scaled by this amount

            float scaleheight = windowaspect / targetaspect;

            // obtain camera component so we can modify its viewport

            Camera camera = GetComponent<Camera>();

            // if scaled height is less than current height, add letterbox

            if (scaleheight < 1.0f)
                Rect rect = camera.rect;

                rect.width = 1.0f;

                rect.height = scaleheight;
                rect.x = 0;
                rect.y = (1.0f - scaleheight) / 2.0f;

                camera.rect = rect;

            else // add pillarbox
                float scalewidth = 1.0f / scaleheight;

                Rect rect = camera.rect;

                rect.width = scalewidth;

                rect.height = 1.0f;
                rect.x = (1.0f - scalewidth) / 2.0f;
                rect.y = 0;

                camera.rect = rect;


        // Update is called once per frame
        void Update () {


and this doesn’t seem to work as well. What should I do that my game runs smoothly on any screen size.

For starters, anchor your GUI to the canvas. I’m pretty sure you’re going to need to create 2 setups for each screen orientation or lock the screen orientation to one orientation. So, you’ll probably want a script that replaces the positions of your elements based on screen orientation.