python - PayPal Subscription on webapp

Question

I am coding a web application and I need to make some subscriptions plan using PayPal and Stripe but I have some doubts. First of all how will know my application that user X use subscribed with y paypal account? I can make an endpoint to save this in the database but I do not know how actually to transmit this data to my endpoint once a user started his monthly subscription. Second of all how do I handle the cancel of the service from the user? If he has no money on the paypal account and paypal won't let him pay, does his account go negative or does paypal block the money? How do I know that the money have been blocked and that he cannot pay and send this data to an endpoint modifing his plan on my database? I have some doubts on how the whole system works since I've never coded something like this

Answer 1

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