You cannot delete your account yourself.
Ask them to do it manually for you, using this contact form: http://www.dexknows.com/info/contactUs.asp
URLS:
http://dexknows.com
Please note that AccountKiller.com is not associated with the business listed on this page. AccountKiller provides easy-to-understand instructions and guides on how to cancel charges and relationships from the list of businesses on our site, we have no affiliation with these businesses.