Hi @Pratyush Sharma,
Thanks! The info you requested:
It's a 2015 Macbook Pro running MacOS Mojave 10.14.6.
I'm running Enpass 6.6.1 (804) MAS version.
I'm using 3 vaults, all synced via WebDAV, 2 of them are shared with another user.
I'm using Enpass in "Match device language", and MacOS is set to English (UK).
I'm not sure how to check if the category is a custom or pre-defined one. It's called "Official" but I can't remember if I made that myself or not. When I right-click on it in the sidebar I have a contextual option to Rename, Change Icon, or Delete.