Once a Jira Service Management project has been deleted, it can only be recovered by reinstating a backup or an XML copy. This isn't the most fun thing to do, so make sure you're prepared to delete the project's issues, versions, and components. Associated schemes, workflows, issues types, or any content that could be shared with another project won't be affected.
- Go to your project and click Project settings.
- Select Details from the sidebar.
- Choose Delete project.