To delete your account, go to legacy.songza.com and log in to your account. Click the username on the top right of the screen, then click "Settings". From there, you'll see fields to edit your username, password, email address, etc. Scroll to the bottom and you’ll see a red button labeled “Delete Account”. click on this and you will be all set. Once you delete an account you will not be able to reuse the email address or username associated with the account.
Please note that once an account has been deleted only a Songza administrator has the ability to reinstate it.