Proceed to System Configuration > Setup Required Fields
NOTE: If the Setup Required Fields option does not appear, it will need to be enabled for the Property. For more information on this, please see the article Required Fields Permission in the System Configuration manual.
The Customize Guest Profile Fields box will appear. This box contains a list of all the fields in the PMS that can be made mandatory when creating a reservation. Fields with boxes that are checked are currently set as Required Fields when making a reservation.
To remove a Required Field, double click the check-box under the Required column to de-selct the desired fields. In the below example, Zip was de-selected, and will no longer be required to make a reservation.
Click OK to save.