Through my many travel, I've been issued various certificates, sometime with expired certificates, and sometime with unvalidated certificates. Perhaps they were the only ones readily available at the station, or maybe the station issuing the voucher didn't have time to validate the certificates.

What course of action do the passenger have when we are issued such certificates? I've tried and redeem expired certs for mileage credit, sometimes with a note of my explanation and have never had any problem, but I've never provided such certificates at merchant thinking I will provide unnecessary hassle.

Jiburi