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What is the process of Domestic RoundTrip Booking in SRDV API?
In case of domestic roundtrip you must hit the search API as per the document, you will get 2 ResultIndex, one for Outbound flight and second for Inbound flight, you must hit the FareQuote API two times, one with the OB ResultIndex and second for the IB ResultIndex. Also you must hit the LCC or GDS booking APIs twice, one with the OB ResultIndex and second for the IB ResultIndex.
In case of International roundtrip, the booking will be done in single slot, same as oneway.