How do recurring payments work?
Automatically charging a saved payment method on a schedule (memberships, SaaS plans, instalments).
Recurring billing charges a saved payment method on a schedule without the customer being present. In Malaysia that is usually a tokenised card; bank-transfer rails like FPX are customer-initiated, so they do not support background charges in the same way.
A good recurring setup handles more than the happy path: failed-charge retries, card-expiry updates and cancellation flows. Gateways with a subscription API do this for you; with a bare charge API you schedule and retry yourself.