We are aware of the issue where you cannot install fences after the maintenance on Nov 17 (Wed) and a message stating, "Cannot install in Conquest/Node War areas" is displayed.
The issue will be fixed with next week's maintenance. Please check the following image for areas in which you cannot install fences.
We apologize for the inconvenience and will strive to provide a better service.
[Notice] [Completed] November 24, 2021 (Wed) Service Maintenance Notice 2021-11-22
[Notice] [Resolved] Unable to log into the official website/game through the launcher 2021-11-21
[Notice] [Completed] November 17, 2021 (Wed) Service Maintenance Notice Last modified: 11/16 16:05 2021-11-15
[Notice] Node/Conquest War Pre-Season Extension 2021-11-12