NEWJOSSY

[river plank]

The payment for the Invoice would fail: https://stripe.com/docs/billing/subscriptions/overview#requires-payment-method

[misty gale]

Okay, if user attaches new payment method after deleting, what should we do? As I see from documentation Stripe will keep latest invoice as open

https://stripe.com/docs/billing/subscriptions/overview#unpaid-subscriptions

[river plank]

You will need to bring the customer back on-session and manually re-confirm the Payment Intent associated with the Invoice. It's outlined here: https://stripe.com/docs/billing/subscriptions/webhooks#payment-failures

[misty gale]

Sorry need one more thing to clarify

I'll describe some cases

Case 1: User has 2 payment methods. We want user to set one payment method to set as primary or default. How can we achieve this?
Case 2: User has 1 payment method. User purchased a subscription with this payment method and then deleted it, and then added new one before his next payment date. How can we use that newly added payment method for subscription payment in upcoming invoice?

[river plank]

Case 1: User has 2 payment methods. We want user to set one payment method to set as primary or default. How can we achieve this?
You'd update this field on the Customer object: https://stripe.com/docs/api/customers/object#customer_object-invoice_settings-default_payment_method
Case 2: User has 1 payment method. User purchased a subscription with this payment method and then deleted it, and then added new one before his next payment date. How can we use that newly added payment method for subscription payment in upcoming invoice?
You'd need to update the default PM on either the Subscription (https://stripe.com/docs/api/subscriptions/update#update_subscription-default_payment_method) or at the Customer level (as above).

[misty gale]

Thanks for clarifying