Payment links and gateways
A hotel takes money its own way — Razorpay or PhonePe on its own account — with a link the guest can settle from before they arrive, receipted straight to the folio.
Every hotel already has a payment provider, chosen before it chose a PMS. So the product does not have a gateway; it has a module for each provider, and a hotel connects its own account.
What a link does
A booking can carry a request for money — an advance, a deposit, the full stay. The guest gets a link by email; the gateway takes the payment; the result lands on the folio as a receipted payment with the method and the gateway's reference, and the hold on the room becomes a confirmed booking.
What happens when nothing arrives
The attempt is chased until somebody knows: the system asks the gateway again, records every attempt, and when the hold's hour passes with nothing paid, the room goes back on sale. A payment that arrives late, or twice, is matched to its attempt and never taken twice.
In the books
The gateway pays out net. The difference between what the guest paid and what reached the bank is the fee, and the books post it as a fee against the gateway's control account when the settlement is matched — the ₹10,000 the guest paid and the ₹9,764 the bank received are both explained.
Providers today
Razorpay and PhonePe. A provider is a module against a registry; the next one is the next module.