Want to do a little cleaning? There are several options available to you. 

If you are inside a lease that is being created, use the trash can icon located at the top right of the screen in the lease: 

Another possibility when you are in the "My leases" tab. In the right section of each lease in your list you will see 3 small dots. By clicking these 3 dots you will have the possibility to delete the lease, whatever its status: 

Once you press "delete", you will get a confirmation message for the deletion of your desired lease: 

You should know that it is the same principle to delete a lease, regulation, or annex templates.