Custom Shader, doesn`t receive Light "Blend3TextureBase"

Hello! I have a custom shader, thats blending 3 textures, 2 Textures and one LightMap.

The problem, is that this shader doesn`t receive light. I tryed 2 days to modify it, but when i try to add #pragma surface surf lambert, it tells me that "#pragma surface does not allow specifying other programs at line".

I can`t use another shader, because after the map will be very ugly. I will attach here the shader code, maybe someone can tell me how to edit it.

Thank you!

 Shader "Marius/BlendTexturBase" {
 Properties {
 
     _MainTex ("Texture 1", 2D) = "white" { }
     _SecTex ("Texture 2", 2D) = "white" { }
     
     _LightMap ("Lightmap", 2D) = "white" { }
     _LightIntensity ("Lightmap Intensity", Float) = 1.0
 }
 SubShader {
     Tags { "Queue"="Geometry" "IgnoreProjectors"="True" "RenderType"="Opaque" }
      LOD 300
     Pass {
     
 CGPROGRAM
 #pragma vertex vert
 #pragma fragment frag
 #pragma exclude_renderers d3d11 xbox360 ps3 flash 
 #pragma fragmentoption ARB_precision_hint_fastest
 #pragma glsl_no_auto_normalization 
 #include "UnityCG.cginc"
 
 sampler2D _MainTex;
 sampler2D _LightMap;
 sampler2D _SecTex;
 
 fixed _LightIntensity;
 fixed _SliderTexture;
  
 
 
 struct a2f 
 {
     float4 vertex : POSITION; 
     float2 uv_main : TEXCOORD0;
     float2 uv_light : TEXCOORD1;
 
 }; 
 
 struct v2f 
 {
     float4 vertex : SV_POSITION;
     float2 uv_main : TEXCOORD0;
     float2 uv_light : TEXCOORD1;
     float2 uv_sec : TEXCOORD2;
 
 };
 
 
 uniform float4 _MainTex_ST; 
 uniform float4 _SecTex_ST;
 
 
 
 v2f vert (a2f v)
 {
 
     v2f o;
     
     o.vertex = mul(UNITY_MATRIX_MVP, v.vertex);
     o.uv_light = v.uv_light;
     
      o.uv_main = TRANSFORM_TEX (v.uv_main, _MainTex);
      o.uv_sec = TRANSFORM_TEX (v.uv_main, _SecTex);
     
     return o;
 }
  
 
 fixed4 frag( v2f i ) : COLOR
 {
     float4 main = tex2D (_MainTex, i.uv_main);
     float4 sec = tex2D (_SecTex, i.uv_sec); 
     
     float4 light = tex2D (_LightMap, i.uv_light);
     float4 main2 = lerp (main , sec,  light.a);
     
     
     return main2 * light * _LightIntensity;
 }
 
 
 ENDCG
     }
 } 
 }