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What happens if "PartialCancellationAllowed": true and the user cancels the Lead Passenger?
If "PartialCancellationAllowed": true, and the lead passenger is cancelled, the entire booking will be automatically cancelled.. This is because the lead passenger is considered the main holder of the reservation, and removing them can invalidate the booking for all other passengers.
Note: To avoid full cancellation, it is recommended to cancel only non-lead passengers when partial cancellation is required.