Here are few steps to delete your existing account:
On dashboard, you will find Accounts then click on Account Details.
There is a button "Delete", click on the particular account details Delete button to delete the account.
When you will click on Delete button then you will receive a message "Do you want to delete your account", if yes then click on "OK" and if you want to cancel it, click on Cancel.
If you have any further queries, please feel free to contact us at firstname.lastname@example.org