- Make sure Emissive Light Source is enabled on the meshes that emit the light:
- Make sure the meshes with Emissive materials have Nanite enabled
- Try increasing Lumen Scene Detail in the Post Process Volume Lumen settings:
If none of the above help, it is likely that the Light meshes are still getting culled from the lumen scene at distance. You can force them to cull at much larger distance by increasing their bounds in the Static Mesh Editor: