Error: you are pushing more GUIClips than you are poping.

I have no idea what this means…
I have an inventory system that used GUI buttons and i get this error whenever i hit play.

If you know what the problem is THANKS IN ADVANCE!

No specific line for the error

#pragma strict
 
var Ammount : int[] = [0,0,0,0];
var ItemTransform : Transform[];
var NewTexture : Texture[];
var AllTextures : Texture[];
var InventoryGrid : int;
var GridNumber : int;
var AddingItems = false;
var MouseTexture : Texture;
var Change = false;
var HotBarActive : int = 35;
var PrevTexture : int;
var TextureNumber : int;
var item : Texture;
var ItemNumber : int;
private var ItemID : String[] = ["Wood","Stone","Metal Ore","Iron"];
private var Blank : Texture;
private var Clicks : int;
private var PrevNo : int;
private var InventoryOn = false;
private var JustClicked = false;
 
 
 
function ADDTexture(ItemTexture : Texture)
{
    item = ItemTexture;
    AddingItems = true;
}
 
 
 
function ADD(material : int)
    {
         material = ItemNumber;
       Ammount[material] +=1;
    }
 
 
    function OnGUI()
    {
    if(InventoryOn == true)
         {
         GUI.Label(Rect(Input.mousePosition.x - 25, Screen.height - Input.mousePosition.y - 25 ,100,50),MouseTexture);
 
         GUI.BeginGroup(new Rect(Screen.width / 2 - 400, Screen.height /2 - 300,800,600));
 
         if(GUI.Button(Rect(100,50,50,50),NewTexture[0]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 0;       
         }
         if(GUI.Button(Rect(150,50,50,50),NewTexture[1]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 1;       
         }
         if(GUI.Button(Rect(200,50,50,50),NewTexture[2]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 2;  
         }
         if(GUI.Button(Rect(250,50,50,50),NewTexture[3]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 3;  
         }
         if(GUI.Button(Rect(300,50,50,50),NewTexture[4]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 4;  
         }
         if(GUI.Button(Rect(350,50,50,50),NewTexture[5]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 5;  
         }
         if(GUI.Button(Rect(400,50,50,50),NewTexture[6]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 6;  
         }
         if(GUI.Button(Rect(100,100,50,50),NewTexture[7]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 7;  
         }
         if(GUI.Button(Rect(150,100,50,50),NewTexture[8]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 8;  
         }
         if(GUI.Button(Rect(200,100,50,50),NewTexture[9]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 9;  
         }
         if(GUI.Button(Rect(250,100,50,50),NewTexture[10]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 10; 
         }
         if(GUI.Button(Rect(300,100,50,50),NewTexture[11]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 11; 
         }
         if(GUI.Button(Rect(350,100,50,50),NewTexture[12]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 12; 
         }
         if(GUI.Button(Rect(400,100,50,50),NewTexture[13]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 13; 
         }
         if(GUI.Button(Rect(100,150,50,50),NewTexture[14]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 14; 
         }
         if(GUI.Button(Rect(150,150,50,50),NewTexture[15]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 15; 
         }
         if(GUI.Button(Rect(200,150,50,50),NewTexture[16]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 16; 
         }
         if(GUI.Button(Rect(250,150,50,50),NewTexture[17]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 17; 
         }
         if(GUI.Button(Rect(300,150,50,50),NewTexture[18]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 18; 
         }
         if(GUI.Button(Rect(350,150,50,50),NewTexture[19]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 19; 
         }
          if(GUI.Button(Rect(400,150,50,50),NewTexture[20]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 20; 
         }
         if(GUI.Button(Rect(100,200,50,50),NewTexture[21]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 21; 
         }
         if(GUI.Button(Rect(150,200,50,50),NewTexture[22]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 22; 
         }
         if(GUI.Button(Rect(200,200,50,50),NewTexture[23]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 23; 
         }
         if(GUI.Button(Rect(250,200,50,50),NewTexture[24]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 24; 
         }
         if(GUI.Button(Rect(300,200,50,50),NewTexture[25]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 25; 
         }
         if(GUI.Button(Rect(350,200,50,50),NewTexture[26]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 26; 
         }
         if(GUI.Button(Rect(400,200,50,50),NewTexture[27]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 27; 
         }
          if(GUI.Button(Rect(100,250,50,50),NewTexture[28]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 28; 
         }
         if(GUI.Button(Rect(150,250,50,50),NewTexture[29]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 29; 
         }
         if(GUI.Button(Rect(200,250,50,50),NewTexture[30]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 30; 
         }
         if(GUI.Button(Rect(250,250,50,50),NewTexture[31]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 31; 
         }
         if(GUI.Button(Rect(300,250,50,50),NewTexture[32]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 32; 
         }
         if(GUI.Button(Rect(350,250,50,50),NewTexture[33]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 33; 
         }
          if(GUI.Button(Rect(400,250,50,50),NewTexture[34]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 34; 
         }
 
          if(GUI.Button(Rect(400,350,50,50),NewTexture[40]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 40;
         }
 
          if(GUI.Button(Rect(450,350,50,50),NewTexture[41]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 41;
         }
 
          if(GUI.Button(Rect(500,350,50,50),NewTexture[42]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 42;
         }
 
              if(GUI.Button(Rect(600,350,50,50),NewTexture[43]))
              {
              if(MouseTexture == Blank)
              {
              if(NewTexture[43] !=Blank)
              {
              JustClicked = true;
              NewTexture[40] = Blank;
              NewTexture[41] = Blank;
              NewTexture[42] = Blank;
              }
         Change = true;
         Clicks += 1;
         GridNumber = 43;
         }
         
         Debug.Log(Clicks);
        
 
 
 
         GUI.EndGroup();
         }
         if(GUI.Button(Rect(100,550,65,65),NewTexture[35]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 35;
         }
         if(GUI.Button(Rect(165,550,65,65),NewTexture[36]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 36;
         }
         if(GUI.Button(Rect(230,550,65,65),NewTexture[37]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 37;
         }
         if(GUI.Button(Rect(295,550,65,65),NewTexture[38]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 38;
         }if(GUI.Button(Rect(360,550,65,65),NewTexture[39]))
         {
         Change = true;
         Clicks += 1;
         GridNumber = 39;
         }
    }
    }
 
 
 
function Update () 
       {
 
       if(Input.GetKeyDown(KeyCode.Alpha1))
       {
       HotBarActive = 35;
       }
       if(Input.GetKeyDown(KeyCode.Alpha2))
       {
       HotBarActive = 36;
       }
       if(Input.GetKeyDown(KeyCode.Alpha3))
       {
       HotBarActive = 37;
       }
       if(Input.GetKeyDown(KeyCode.Alpha4))
       {
       HotBarActive = 38;
       }
       if(Input.GetKeyDown(KeyCode.Alpha5))
       {
       HotBarActive = 39;
       }
 
    if(NewTexture[HotBarActive] == AllTextures[TextureNumber])
    {
    PrevTexture = TextureNumber;
    ItemTransform[TextureNumber].active = true;
    }
 
    if(NewTexture[HotBarActive] != AllTextures[TextureNumber])
       {
       ItemTransform[PrevTexture].active = false;
       TextureNumber += 1;
       if(TextureNumber >= AllTextures.Length)
          {
          TextureNumber = 0;
          }
       }
 
    if(NewTexture[40] == AllTextures[0] && NewTexture[41] == Blank && NewTexture[42] == AllTextures[0])
         {
         NewTexture[43] == AllTextures[3];
       }
       
 
if(Input.GetKeyDown(KeyCode.Tab))
    {
    InventoryOn = !InventoryOn;
    }
    if(AddingItems == true)
       {
         if(NewTexture[InventoryGrid] == Blank)
                   {
                   NewTexture[InventoryGrid]=item;
                   AddingItems = false;
                   InventoryGrid = 0;
                   }
          else if(NewTexture[InventoryGrid] != Blank)
          {
          InventoryGrid += 1;
          }
       }

         
         
         if(Clicks == 0)
   {
   MouseTexture = Blank;
   }
   
      					if(Clicks == 1)
                        {
                        MouseTexture = NewTexture[GridNumber];
                        PrevNo = GridNumber;                                            
                        }
                       
                        if(Clicks == 2)
                        {
                        if(NewTexture[GridNumber] != Blank)
                        {
                        Clicks = 1;
                        }
                         if(NewTexture[GridNumber] == Blank)
                         {
                         
                        NewTexture[GridNumber] = MouseTexture;
                        NewTexture[PrevNo] = Blank;
                        Clicks = 0;
						}
					}
				}

Your GUI.EndGroup in line 302 is inside one of your buttons. It looks like you messed up your brackets. I suggest to use a consistent indent style to avoid such errors in the future.