From their FAQ, about account deletion:
You can cancel your subscription by logging in to the My Account page and selecting the Cancel My Subscription option or by writing to Member Support: firstname.lastname@example.org.
Besides, from their PP: to correct, update, or remove personally identifiable information, please email us at email@example.com.
However, and as usual, you should note:
We retain your information for as long as necessary to permit us to use it for the purposes that we have communicated to you and comply with applicable law or regulations.