Thank you for pointing out this issue.
The issue is being caused due to DNI field being mandatory during automatic address creation.
In order to resolve this issue, you can disable DNI requirement for corresponding hotel countries.
- To disable DNI requirement, go to Hotel Reservation System > Manage Hotel and note down countries for all added hotels.
- Then go to Localization > Countries and search for noted countries.
- Edit that country and set the following field 'Do you need a tax identification number?' at the bottom to NO.
- Repeat for all the countries noted above.
Try booking now and let us know if you still encounter this issue.