Why does object shadow disappear when its further from light source?

I have an actor that has a Runtime Mesh Component attached. The mesh in the RMC will cast shadows when it is close to the light source but when it is further away it stops. Why?

The distance is between 1000 - 30,000 units. I’ve noticed that when I mess with the shadow bias up to like 15 I get shadows when the RMC is close to the light. If the shadow bias is lower around 1, I get strange striations across the world geometry. I know this isn’t the intended use of this property but it’s the only way I’m seeing shadows so far.