The message "You have an upcoming appointment scheduled for Invalid date" is displayed when using the "walkup_online_checkin" page of the service portal to book an appointmentDescriptionIf you use the "walkup_online_checkin" page of the service portal to book an appointment, the message "You have an upcoming appointment scheduled for Invalid date" is displayed. A specific date and time should be displayed on the message instead of showing "Invalid date".Steps to Reproduce The issue can be reproduced in the OOB Madrid and New York with the following steps:1. Activate the system plugins "Walk-up Experience" (com.snc.walkup) and "Appointment Booking" (com.snc.appointment_booking).2. Set the system property "glide.sys.date_format" to the value "dd/MM/yyyy".3. Login as the user "Walk-up Experience".4. Go to the walkup page and select a walk-up location, then click on "Check-in".https://XXXXXXX.service-now.com/walkup?id=walkup_check_in&location_id=XXXXXXXXXXXXXXXXXXX5. Go to the "walkup_online_checkin" page of the service portal by replacing "walkup_check_in" with "walkup_online_checkin" in the above mentioned URL.https://XXXXXXX.service-now.com/walkup?id=walkup_online_checkin&location_id=XXXXXXXXXXXXXXXXXXX6. Click on the tab "Schedule an appointment" and schedule an appointment.7. Click on the tab "Join the queue", you will see the message "You have an upcoming appointment scheduled for Invalid date".The expected behaviour is that a specific date and time should be displayed on the message instead of showing "Invalid date".WorkaroundThis issue is under review. To receive notifications when more information is available, subscribe to this Known Error article by clicking the Subscribe button at the top right of the article. If you are able to upgrade, review the Fixed In or Intended Fix Version fields to determine whether any versions have a planned or permanent fix.Related Problem: PRB1356669