Hello, RealRoachPlay, let me help you with this.
The level is not configured to use external actors (One File Per Actor), which is necessary for World Partition functionality. In Unreal Engine 5, enabling the “Use External Actors/Objects” option in the level settings is essential for World Partition to work properly.
If it is enabled, change it to disable.
PD: Please create a backup of the project before proceeding.
Here is the link to the forum discussing this topic.
One File Per Actor doc:
https://dev.epicgames.com/documentation/en-us/unreal-engine/one-file-per-actor-in-unreal-engine?application_version=5.0
DataLayers:
Feel free to share if you’re still facing challenges or have new questions.