Idiotic UX UI failure, why can't I rename my gateway? What a complete waste of time, thanks for forcing me to delete all kinds of work just to appease a stupid name change
Gateways are referenced by name in places like static routes and firewall rules. Renaming a gateway could break your configuration.
What you can do: Download a config backup, use search & replace to rename the gateway everywhere, reimport the config.
Cheers
Maurice