Members have experienced getting "Invalid ID" error while trying to register at https://managebooking.mandai.com/redemption-portal-member before 16th April 6pm.
We have been confirmed by Mandai Booking that the wrong Pass IDs issued. We have updated the Pass IDs You may login and reprint your authorisation letter via "My Account"->"My Reserved Passes".
You can register at Mandai's portal. Make sure that you enter the correct Pass ID and select the correct visitation date, the same date that is in your authorisation letter.