Can't fix Black Walls Lighting issue no matter what

I tried multiple things but still can’t figure out how exactly I’m supposed to fix this:

  • I surrounded the level with a Lightmass Importance Volume.
  • I placed a Sky Light in the level.
  • I enabled the “Shadow Two Sided” option in the mesh settings.
  • I tried creating a new UV Channel and packed my lightmap there.
  • I tried using Unreal’s Generate Lightmap UVs in the mesh properties with resolution 512 on index 1
  • I tried changing lighting quality to “Production”
  • I set the Quality under Engine Scalibility to “Epic”
  • I even tried using stock cube mesh which supposedly already comes with a pre-configured light settings.

Yet I still get this issue? Please help!