You can view and cancel your subscription purchased through Apple following the instructions for your device here.
You can view and cancel your subscription purchased through Google Play following the instructions here.
The Tapping Solution is not able to manage or cancel your subscription for you if you purchase through Google Play or Apple.
The Tapping Solution
If you purchased the App through The Tapping Solution directly you can view and cancel your subscription at https://www.thetappingsolutionapp.com/premium/login.php
Please note in order to avoid your subscription renewing you need to cancel more than 24 hours before your renewal date.