Lighting error on procedural mesh

Hello, was wondering if I could have a little help.

I’m currently trying to make procedural terrain in UE4. I’m having an issue however with light bleeding from the edges of the mesh if the directional light moves behind it. I have tried using a two sided material and generating back facing pollys but to no success. Any Ideas why this may be happening? Both the directional light and skylight are movable.

Thank you for your help

This is more of a question for the Rendering subforum, as it has to do with the shadows - its no fault of your code. The problem you are experiencing is actually somewhat common in UE4. They should be able to help you better.

Thank you for letting me know its not my code being an issue. Ill move it over to the rendering subforum now.