Here is how to cancel an automatic payment if you subscribed to SeriousMD using Paypal:
Log in to your PayPal account.
Click the Settings icon next to "Log out."
Click the Payments tab, then click Manage pre-aproved payments under "Pre-approved payments."
Select the payment you'd like to cancel, then click Cancel.
This will stop your Paypal from paying again on the next billing cycle.
Your SeriousMD account will downgrade to the Free plan after the cycle ends.
You can also request for the support team to do this for you.