> For the complete documentation index, see [llms.txt](https://developer.rategain.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.rategain.com/ultradirect/ultradirect-transaction-sets-xml/booking-transactions/request-message-format-modify.md). # Request message format - Modify
Element PathAttributeOccTypeNotes

HotelML/Head/Process

1

DataPath

1

Char

Set to "/HotelML/Form/ModifyReservation”

Function

1

Char

Set to “TI_ModifyReservationV1_1”

Token

1

Char

Unique ID for the transaction generated by the system sending the transaction.

HotelML/Head/Route

1

Source

1

Char 2-3

Identifies the organization sending the transaction. The value to use will be provided during the implementation project.

Destination

1

Char 2

Always set to “00” (i.e. zero zero).

HotelML/Form/ModifyReservation

Session

0..1

Enum

Set to “New” if using active session control (i.e. booking will not be confirmed until committed using the SessionControl message). Otherwise omit the attribute.

HotelML/Form/ModifyReservation/Res ervation

1

The Reservation element is used to identify the booking to be modified. This includes the confirmation number plus other information to verify the booking (e.g. arrival/departure dates, guest name etc.)

Confirmation Number

1

Char 6-80

CRS confirmation number

InDate

1

Date

Arrival date

OutDate

1

Date

Departure date

PropertyCode

1

Char 10

Chain and property code – e.g. “UI;12345”

HotelML/Form/ModifyReservation/ Locale

0..1

This is used to request the response in a specific language.

Note: It can only be included if requesting a language other than English.

Language

1

Char 2

Language code – e.g. “FR”


Country

0..1

Char

Optional country name – e.g. “France”.

HotelML/Form/ModifyReservation/ Reservation/Guest

1

Name of primary guest

FirstName

1

Char 99

Guest’s first name or initials. Total length of FirsName + LastName cannot exceed 99 characters

LastName

1

Char 99

Guest’s last name

HotelML/Form/ModifyReservation/ UpdateReservation

1

The UpdateReservation element contains a full recap of the booking, containing both changed and unchanged information. The content of this element and all child elements is exactly the same as the BookReservation element (and so not repeated here) except that the PropertyCode and Session attributes are not used.

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