Error:

$additional_guest_spinbox was NULL when evaluating $additional_guest_spinbox.getValue()

Debug Info:
- Registered Vars:

[
	"_SERVER", 
	"_GET", 
	"_POST", 
	"_COOKIE", 
	"_SESSION", 
	"_REQUEST", 
	"_ENV", 
	"postMain", 
	"arrAttendee", 
	"event", 
	"event_product", 
	"currency", 
	"arrContact", 
	"attendance_status_combobox_update_event", 
	"product_order_options_ajax", 
	"rsvp_form", 
	"contact_id", 
	"event_attendee_id", 
	"attendance_status_combobox", 
	"current_name_changed_event", 
	"contact_representing_company_region", 
	"attendee_contact_company_id", 
	"attendee_contact_company", 
	"attending_contact_details_form", 
	"contact_first_name", 
	"contact_last_name", 
	"contact_email", 
	"contact_phone", 
	"event_id", 
	"showhide_alternate_rsvp_region", 
	"alternate_contact_form", 
	"alternate_first_name_editbox", 
	"alternate_last_name_editbox", 
	"alternate_email_editbox", 
	"alternate_phone_editbox", 
	"additional_guests_region", 
	"payment_region"
]

Possible Solutions:
- Catch this exception (Framework\DOM\Features\Scripting\Exceptions\InScript)

in /usr/lib/php/Oncord/stable/Scr/OpObjectDereference/OpObjectDereference.inc.php line 45