We firmly suggest you enter valid and up-to-date contact data of each passenger in the reservation, the concerned travel advisors, as well as other contacts that may be reached in case of urgency.
By saying the contact information is essential for a successful trip, we by no means tend to exaggerate. However, unexpected issues that require quick actions may happen at any moment, and the contact information is the best way to transmit the updates to you in a timely manner. Please, provide us with any supplementary contact data that may help us send you the updates in such a way that it will reach the intended recipients faster. (These may contain: alternate email addresses; phone numbers that are used internationally or at the destination, the contact information of a family member you're staying in contact with the most, trip organizer, etc.)