How to make surface shader receive shadows?

Hello! I have a surface shader, which blends some textures. It doesn't receive shadows. What is the problem?

 Shader "Custom/TextureBlend" {
     Properties {
         _Color ("Color", Color) = (1,1,1,1)
         _NoiseTex ("NoiseGREY", 2D) = "asd" {}
         _SandTex ("Sand", 2D) = "sdf" {}
         _SnowTex ("Snow", 2D) = "dfg" {}
         _GrassTex ("Grass", 2D) = "dfg" {}
         _Glossiness ("Smoothness", Range(0,1)) = 0.5
         _Metallic ("Metallic", Range(0,1)) = 0.0
         _BlendSmoothness ("BlendSmoothness", Range(1,50)) = 0.0
     }
     SubShader {
         Tags { "RenderType"="Opaque" "Queue" = "Geometry"  }
         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 _NoiseTex;
         sampler2D _SandTex;
         sampler2D _SnowTex;
         sampler2D _GrassTex;
 
         struct Input {
             float2 uv_NoiseTex;
             float2 uv_SandTex;
             float2 uv_SnowTex;
             float2 uv_GrassTex;
         };
 
         half _Glossiness;
         half _BlendSmoothness;
         half _Metallic;
         fixed4 _Color;
 
         // Add instancing support for this shader. You need to check 'Enable Instancing' on materials that use the shader.
         // See https://docs.unity3d.com/Manual/GPUInstancing.html for more information about instancing.
         // #pragma instancing_options assumeuniformscaling
         UNITY_INSTANCING_CBUFFER_START(Props)
             // put more per-instance properties here
         UNITY_INSTANCING_CBUFFER_END
 
         void surf (Input IN, inout SurfaceOutputStandard o) {
             // Albedo comes from a texture tinted by color
             float4 inp = tex2D(_NoiseTex, IN.uv_NoiseTex);
             float m = 2.0;
             float _m = 1 / m;
 
             uint sh = inp.r > 0.5;
             uint fh = inp.r <= 0.5;
             float4 a = atan((inp - _m / 2 - _m * sh) * _BlendSmoothness) * 0.364 + 0.5;
             float4 c = (tex2D(_SnowTex, IN.uv_SnowTex) * sh + tex2D(_SandTex, IN.uv_SandTex) * fh) * a * m;
             c += (tex2D(_SandTex, IN.uv_SandTex) * sh + tex2D(_GrassTex, IN.uv_GrassTex) * fh) * (1 - a) * m;
             o.Albedo = c.rgb;
             o.Metallic = _Metallic;
             o.Smoothness = _Glossiness;
             o.Alpha = 1;
         }
         ENDCG
     }
     FallBack "Diffuse"
 }