worldPos in shader giving errors when game is paused

I am working on a voxel game, and I want it so that the player sees further than the loaded voxels, so I made a big circle in blender that has a hole in the middle, where the loaded terrain is. The circle mesh puts every point in it to an y coordinate that is generated with perlinnoise (transform.posx + vert.posx,..............) , So its basically an easy to make LOD system thing cause the points in the circle are less dense on the edges than near the middle. I made a material that has a shader that renders sand under y < 19 and it renders grass above. I used WorldPos in the shader, and when I pause the game it gives the following error: rc.right == m_GfxWindow->GetWidth() && rc.bottom == m_GfxWindow->GetHeight() Why is it giving that error? What does my shader need to check for when the game is paused so it gives no error? Here is the code:

     Properties {
         _Color ("Color", Color) = (1,1,1,1)
         _MainTex ("Albedo (RGB)", 2D) = "white" {}
         _Glossiness ("Smoothness", Range(0,1)) = 0.5
         _Metallic ("Metallic", Range(0,1)) = 0.0
     }
     SubShader {
         Tags { "RenderType"="Opaque" }
         LOD 200
         
         CGPROGRAM
         // Physically based Standard lighting model, and enable shadows on all light types
         #pragma surface surf Standard fullforwardshadows
 
         // Use shader model 3.0 target, to get nicer looking lighting
         #pragma target 3.0
 
         sampler2D _MainTex;
 
 
 
         struct Input {
             float3 worldPos;
             float2 uv_MainTex;
         };
 
         float2 pluss;
 
 
 
         half _Glossiness;
         half _Metallic;
         fixed4 _Color;
 
         void surf (Input IN, inout SurfaceOutputStandard o) {
         if(IN.worldPos.y > 19){
         pluss.x = -0.3751f;
         }else{
         pluss.x = 0;
         }
             // Albedo comes from a texture tinted by color
             fixed4 c = tex2D (_MainTex, IN.uv_MainTex + pluss) * _Color;
             o.Albedo = c.rgb;
             // Metallic and smoothness come from slider variables
             o.Metallic = _Metallic;
             o.Smoothness = _Glossiness;
             o.Alpha = c.a;
         }
         ENDCG
     }
     FallBack "Diffuse"
 }

Here is an image: