If you don't want to stay in a Workspace, you can feel free to leave it.
- Sign in to your Awesome Screenshot account
- Go to "My items" and click on the name of the Workspace that you want to leave
- Hit "Settings", find "Leave Workspace" and click on "Leave"
Please note that only members can leave a Worspace. If you are an admin/owner of a Workspace, you can only delete it instead of leave it.