We feel sorry to know that you want to leave slice. Nevertheless, you can deactivate your slice profile by following these steps :
Open your slice app, click on profiles. (You can find that option on the bottom of the screen) make sure you are logged in to the right account.
Click on settings ~> Deactivate Account ~> Enter OTP.
Your account would be deactivated after that. After that is done you would not receive any further communication from us.
Please Note: You need to make sure that you do not have any due amount. You can still create an account if you wish to, but you might not get re-approved if you were waitlisted before the deactivation and did not provide the appropriate details in the second attempt.