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Which steps we have to follow for LCC and GDS?
If you will get IsLcc= True (In search response) that means it is a LCC flight so no need to to call GDS API, you must follow the LCC booking process(1. Search, 2. FareRule, 3. FareQuote, 4. SSR, 5. Book LCC).
If IsLcc= False (In search response) that means it is a GDS flight then you must follow the GDS booking steps(1. Search, 2. FareRule, 3. FareQuote, 4. SSR, 5. Hold, 6. Ticket). Please refer to the below document:
https://www.srdvtechnologies.com/doc/flight/v8/pathway