When you want to use the Booker25 Widget and are currently on a Booker25 version before 4.60 you need to upgrade Booker25 to the latest version before the implementation and perform some post-install steps to support the widget.
Also install the latest Landings page package, Booker25 Widget - Overview.
Post-install
Make sure to adjust the Dimension Junction related to the Contact dimension to use new fields. This Dimension junction is called B25__ReservationContact__c
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