Lighting can't rebuild

I’m having an issue where I’m unable to rebuild lighting. This problem is persistent over every project, regardless of lighting settings.
Whenever I try to rebuild it, I get a message in the bottom left of the window, saying “Lighting build failed.”, and when I go to check to log, there’s another error stating “WorldSettings Maps need lighting rebuilt”.
I looked around to see if anyone was having the same issue, and I didn’t find anything except that it might have something to do with Swarm Agent. I checked the Swarm Agent log, which said “[Interface:OpenJob] Error: Invalid namespace”
I don’t know what to do with this information, so if anyone knows how to solve this, I’d really appreciate it.

Have you tried to build Unreal Lightmass?

I’m new to this, and not exactly sure what you mean. Are you referring to the Lightmass Importance Volume, or do I have to build it in Visual Studio?

You have to build it in Visual Studio. Are you using the engine from source code or from Epic Launcher?

I’m using the launcher. Could you give me a rundown of the steps I need to take?

Try to download the source code version and build UnrealLightmass.
This is a guide on how to build UnrealEngine from source: Building Unreal Engine from Source | Unreal Engine Documentation

I can’t seem to find the source code on GitHub, is it still available anywhere else?

You must be registered on GitHub with the Epic Games repository, in order to do that, follow this tutorial: Unreal Engine 4 on GitHub - Unreal Engine

Hello,

We’ve recently made a switch to a new bug reporting method using a more structured form. Please visit the link below for more details and report the issue using the new Bug Submission Form. Feel free to continue to use this thread for community discussion around the issue.

https://forums.unrealengine.com/unreal-engine/announcements-and-releases/1410408-unreal-engine-bug-submission-form

Thanks