When a noclipping player approaches a teleporter with “ask permission” off, the player will be teleported and will have their noclip flight disabled, causing them to fall through the map.
Approach a teleporter with “ask permission” off while in noclip.
The player isn’t teleported.
The player is teleported, and falls through the map.
Making noclip flight be enabled after teleporting would technically fix the bug, but teleporting on contact with a teleporter while in noclip makes it difficult to edit larger teleporters.