Matrix error

I have this code:

 using UnityEngine;
 using System.Collections;
 
 public class DrawCanvas : MonoBehaviour {
     
     public float sWidth;
     public float sHeight;
     public float GUIRatioX;
     public float GUIRatioY;
     public Vector3 GUIsF;
     public GUISkin skinGUI;
     public int sizeGUI;
 
     void Start(){
         sWidth = Screen.width;
         sHeight = Screen.height;
 
         GUIRatioX = sWidth / 1920 * sizeGUI;
         GUIRatioY = sHeight / 1080 * sizeGUI;
 
         GUIsF = new Vector3(GUIRatioX,GUIRatioY,1);
     }
 
     void OnGUI() {
         GUI.skin = skinGUI;
 
         GUI.matrix = Matrix4x4.TRS(new Vector3(GUIsF.x,GUIsF.y,0),Quaternion.identity,GUIsF);
 
         if(Application.loadedLevelName == "Menu"){
             if(GUI.Button(new Rect(1,4,50,51),"hello")){
                 Debug.Log("pressed");
             }
     }
 }
 }

But it gives this error:

Ignoring invalid matrix assinged to GUI.matrix - the matrix needs to be invertible. Did you scale by 0 on Z-axis? UnityEngine.GUI:set_matrix(Matrix4x4) DrawCanvas:OnGUI() (at Assets/Scripts/DrawCanvas.cs:27)

Why and how can I slove this???