A billing software doesn't initiate a payment request to Paypal with either once off or subscription payments. When you set up a Paypal subscription, that's done at Paypal, which returns a response to our billing software to let it know the payment was made. The recurring payment is done from Paypal, and passes info back again to state a new payment was made against that same subscription ID/email. our billing software matches that and marks invoices paid.
You need to log into Paypal and find the subscription and cancel it. That will end it.
Important: You must do that at least one day before the scheduled date of the next payment. If you fail to do so paypal will continue paying us that does not mean
that our billing software has initiated a payment request to paypal.