put https://api-sandbox.ezypay.com/v2/billing/subscriptions//paymentmethod/
Integrators can this API Endpoint to update a payment method token which has been invalidated. All invoice created by the subscription payment plan will use the updated payment method token.
This API is mostly use when a customer wants to change an old payment method details or the payment method token has been invalidated.
The payment method token used, needs to be linked to the customer Id first before the payment method token can be used.