UE5 World Partition Landscape extremely large – delete freezes editor

Hello,

I accidentally created a very large Landscape (around 10,000–100,000 components)
with World Partition enabled in UE5 (External Actors enabled).

When I try to delete the Landscape from the World Outliner,
the editor becomes extremely slow and never finishes the deletion.
(It does not crash, but seems stuck indefinitely.)

I tried:

  • Deleting the Landscape actor directly
  • Waiting more than 30 minutes
  • Restarting the editor
  • Removing the level and reopening it

Is there a safe or recommended way to remove a huge Landscape
while keeping other actors in the same level?

Any advice would be appreciated.
Thank you.