How do I fix this diffuse shading flip

I have a frag shader and after a bit of rotation the diffuse light shift from one side to another. My guess is that some value is switching a value from positive to negative in one octrant (I think that is what its called) . I have tried to normalize a number of things but as I am newish to this I a missing something. Perhaps a key search term or a bit of knowledge about a function. I keep researching and learning but so far am unable to figure this out.

I made the shader a bit more extreme to show the difference in the seeming flip of the light direction. Any help or pointers would be greatly appreciated. Thanks

 Shader "Unlit/diffuseShader"
 {
     Properties
     {
         _Color("Color", Color) = (1,1,1,1)
         _Gloss("Gloss", Range(0,100)) = 1
         _MainTex("Texture", 2D) = "white" {}
     }
         SubShader
     {
         Tags{ "Queue" = "Transparent" "IgnoreProjector" = "True" "RenderType" = "Transparent" }
         Blend SrcAlpha OneMinusSrcAlpha
 
         Pass
     {
         CGPROGRAM
         #pragma vertex vert
         #pragma fragment frag Standard alpha:fade
         #pragma target 3.0
 
         // make fog work
         #pragma multi_compile_fog
 
         #include "UnityCG.cginc"
         #include "Lighting.cginc"
         #include "AutoLight.cginc"
 
         // Mesh data: vertex position, vertex normal, UVs, tangents, vertex colors
         struct VertexInput {
         float4 vertex : POSITION;
         float3 normal : NORMAL;
         float2 uv0 : TEXCOORD0;
     };
 
     struct VertexOutput {
         float4 clipSpacePos : SV_POSITION;
         float2 uv0 : TEXCOORD0;
         float3 normal : TEXCOOD1;
         float3 worldPos : TEXCOORDS2;
     };
 
 
     float4 _Color;
     float _Gloss;
     uniform sampler2D _MainTex;
 
     // Vertex Shader
     VertexOutput vert(VertexInput v) {
         VertexOutput o;
         o.uv0 = v.uv0;
         o.normal = v.normal;
         o.worldPos = mul(unity_ObjectToWorld, v.vertex);
         o.clipSpacePos = UnityObjectToClipPos(v.vertex);
         return o;
     }
 
     float4 frag(VertexOutput o) : SV_Target{
 
         //return _Gloss;
         float2 uv = o.uv0;
         float3 normal = normalize(o.normal);//Interpolated
 
         //direct Diffuse light
         float3 lightDir = _WorldSpaceLightPos0.xyz;
         float3 lightColor = _LightColor0.rgb;
         float lightFalloff = max(0, dot(lightDir, normal)) ;
         float directDiffuseLight = lightColor * lightFalloff;
 
         // Composite
         //float3 diffuseLight = ambientLight + directDiffuseLight;
         float3 diffuseLight = directDiffuseLight;
         float3 finalSurfaceColor = normalize(diffuseLight * _Color.rgb );
 
         return float4(finalSurfaceColor, 1);
     }
         ENDCG
     }
     }
 }