I need to delete a project which is duplicated please

[Sally Hall]

I can find how to delete boards but not how to delete a duplicated project please advise

[Nic Brough _Adaptavist_]

Log in as an admin, go to the list of projects, find the one you want to remove and go into its admin section.  There's the option to delete in the general project header settings (where you set name, project lead etc).

Bear in mind that this will delete the project and all issues in it irretrievably.  You might want to move issues out of it if there are any, before removal.